Yazar: Süleyman Atılgan

Karda Off Road teknikleri
Off road da Engel Nasıl Aşılmalı ?
Offroad ‘da Ağır Araç mı Hafif Araç mı ?
Denge off-road‘un neresindedir ve önemi nedir ?
Dik çıkış mı daha tehlikeli ? Dik iniş mi daha tehlikeli ?
Yol kenarı Devrilme Analizi
Derin Su Geçişi, Alınması Gereken Tedbirler ve Riskleri Nelerdir ?
Artikülasyon ‘un yol tutuşa etkisi nedir?
4×4 Off-Road Araçlar da Diferansiyelin Önemi Nedir ?
Off-Road Araçlar da “Orta Kilit” ve Önemi Nedir ?
Lastik Büyütme ve Offroad Sürüşüne Etkileri Nelerdir ?
Arazide Hangi Lastiği Tercih Etmeliyim ?
 

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Blog Türkiye

Quel est le différentiel pour les véhicules tout-terrain 4×4 ? Quelle est la grande importance du différentiel?

Tout-terrain et différentiel : Le différentiel est l’un des éléments les plus importants du tout-terrain. La réponse à la raison pour laquelle un véhicule que nous pensons être un 4×4 est en fait un 4×1 est cachée ici. Toute personne qui va sur le terrain devrait avoir ces connaissances de base et interpréter ce qu’elle peut ou ne peut pas faire avec la voiture terrestre dans quelles conditions. Aucune des phrases n’est des citations. Certaines des informations sont originales et uniquement le raisonnement qui appartient à cet article. Ce n’est donc nulle part ailleurs. Notre objectif est d’expliquer le différentiel avec une approche philosophique. La différence entre les différentiels avec des mécaniques différentes ou leurs propres détails n’est pas très important pour nous. L’important est le but de l’utilisation et le service qu’ils fournissent.

Qu’est-ce qu’un différentiel ? Comment fonctionne le différentiel ?

Qu’est-ce qu’un différentiel et pourquoi un différentiel est-il nécessaire ? C’est le nom général du mécanisme qui assure le transfert de puissance aux pneus en tolérant la différence de tour entre les roues lors de la conduite différentielle . Le différentiel ne fait pas tourner les roues à des vitesses différentes ou à la même vitesse, il le permet juste. Lorsqu’un véhicule prend un virage, les 4 roues empruntent des voies différentes. Parce que chaque piste a un rayon différent, toutes les roues tournent à des vitesses linéaires différentes. On peut le voir sur la première photo. S’il n’y a pas de mécanisme interne pour tolérer cette situation, les roues essaieront de tolérer la différence de tour avec des dérapages courts. Ces patins forcent inutilement la transmission du véhicule et provoquent une usure des pneus plus importante que la normale. Si la transmission n’est pas assez solide, elle peut également provoquer des coupures d’essieu ou des ruptures similaires.

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Quel est le principe de fonctionnement principal du différentiel ?

Comment fonctionne le différentiel ? Avant de lire ma réponse à la question, je vous recommanderai de regarder ces deux vidéos.

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Comme expliqué dans les vidéos et compris à partir de la deuxième photo, le joint appelé U-joint (joint universel) à l’extrémité de l’ arbre relie l’arbre à l’arbre conique et l’entraîne. En conséquence, dans le différentiel le plateau commence à tourner . Dans le boîtier du différentiel, 4 pièces d’engrenages d’essieu, 2 chacune 2 dans des directions opposées, et connues sous le nom d’engrenages intermédiaires-engrenages croisés-araignées, etc. Il y a des engrenages . Dans le différentiel, le boîtier est solidaire du rétroviseur. Lorsqu’il est entraîné par l’arbre, le biseau tourne, le mandrin biseauté tourne, le chanfrein fait tourner le boîtier, les pignons fous actionnent les engrenages de l’essieu en poussant, pas en tournant . Faites attention ici . En poussant, pas en tournant. Cela active les deux essieux. En d’autres termes, le mouvement de rotation transféré de la boîte de vitesses au différentiel et de là aux essieux n’est pas un mouvement d’engrenage uniforme tel qu’il est connu. Si, pour une raison quelconque, les essieux ressentent le besoin de tourner différemment, alors les pignons intermédiaires répondent à ce besoin de virages différents non seulement en poussant mais aussi en tournant. C’est le principe de fonctionnement principal du type différentiel le plus connu. Il n’est pas important pour nous quels sont les détails des types différentiels avec des mécanismes différents. L’important est qu’ils fournissent tous le même service. Voici la réponse à la raison pour laquelle nous ne pouvions pas continuer à avancer lorsque le véhicule tombait en diagonale. La puissance du moteur est comme le courant électrique, où la résistance est moindre, elle s’échappe de ce côté. Ainsi, si une roue perd de l’adhérence, elle absorbe toute la puissance du moteur et continue de tourner au ralenti. Pendant ce temps, le véhicule se débat et cale car aucune puissance n’est transmise à la roue qui peut assurer la traction. Bien que cette situation se produise généralement dans la position que nous appelons diagonale, il peut également y avoir des situations où deux roues du même côté ont des problèmes d’adhérence simultanés.

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Quels sont les types différentiels ?

Lorsque vous effectuez des recherches sur le sujet sur Internet, vous rencontrerez les types différentiels suivants dans les sources nationales et étrangères.

1-) Type différentiel ouvert (différentiel ouvert)

2-) Différentiel bloqué

3-) Type de différentiel à glissement limité visqueux (différentiel à glissement limité visqueux)

4-) Type différentiel à glissement limité mécanique ou électrique (LSD de type embrayage mécanique, également eLSD)

5-) Torsen et différentiel hélicoïdal

6-) Différentiel de vecteur de couple

BL bla. Il y a des contradictions conceptuelles dans ces classifications. Par conséquent, j’aborderai le sujet avec une approche différente sans dépendre de ces classifications. Comme je l’ai dit, nous aurons une approche philosophique dans cet article. J’ai expliqué ci-dessus ce qu’est un différentiel et ce dont nous avons besoin dans les véhicules tout-terrain. C’est pourquoi nous allons simplement appeler le différentiel différentiel tout au long de cet article, en tenant compte de la fonction de base du différentiel tout-terrain , quelles que soient les différences dans son principe de fonctionnement.

Qu’est-ce qu’un différentiel bloqué ?

Un différentiel bloqué est un différentiel dont la capacité de tolérance de différence de virage entre l’essieu droit et gauche est réduite ou complètement éliminée , selon la méthode utilisée pour le bloquer. En fait, les types différentiels donnés ci-dessus sont en quelque sorte une variation de ces différences de méthode clés. C’est pourquoi je vais appeler la serrure une serrure. Après tout , quand vous dites différentiel bloqué, vous comprenez, comme je l’ai dit plus haut, “différentiel avec tolérance de différence de tour réduite ou complètement éliminée entre les essieux droit et gauche” . Le mémoire de maîtrise est dérivé des types de serrures et des principes de travail. C’est pourquoi je n’entrerai pas dans trop de détails et je l’examinerai en 4 catégories principales. Les comportements dans ces catégories peuvent être obtenus avec différentes méthodes et structures mécaniques. Ce détail n’est pas très important pour nous. Le service que nous recevons et le résultat sont importants pour nous.

Systèmes différentiels assurant un verrouillage complet dans le véhicule

Ces différentiels assurent un blocage mécanique complet du véhicule et transfèrent la moitié de la puissance du pignon à l’essieu droit et l’autre moitié à l’essieu gauche. La serrure qui nous intéresse le plus est la serrure mécanique . Qu’est-ce qu’une serrure mécanique ? Le principe de base du verrouillage mécanique dans le véhicule est d’empêcher les engrenages des essieux de tourner dans des tours différents . Ceci est facilement réalisé en empêchant la rotation libre des pignons fous. En d’autres termes, quel que soit votre axe gauche tourne, votre axe droit tournera de la même manière. C’est pourquoi nous n’activons jamais de tels verrous sur des surfaces non glissantes afin de ne pas forcer inutilement la mécanique du véhicule dans les virages nécessitant une différence de tours.

Systèmes différentiels assurant un verrouillage partiel dans le véhicule i

Le plus connu est le différentiel LSD. (Différentiel à glissement limité). Ces systèmes différentiels 4×4 servent de manière similaire aux différentiels à blocage complet, mais ils ne peuvent jamais transmettre la puissance de manière égale aux essieux droit et gauche. Ou, dans les systèmes différentiels de certains véhicules, la roue doit être au sol pour que le mécanisme de verrouillage fonctionne. Par conséquent, ils sont plus inefficaces que les systèmes différentiels entièrement verrouillés . En effet, du fait de l’usure mécanique subie dans le temps, sa présence ou son absence est incompréhensible dans les voitures anciennes.

Systèmes différentiels pouvant transférer une puissance différente aux essieux droit et gauche

VLSD (Viscous Limited Slip Differential) , l’e-LSD fait partie de ce groupe de différentiels. Ces systèmes ont différentes capacités de transfert de puissance entre les essieux droit et gauche en fonction des besoins. Dans certains systèmes, le système ne s’active pas jusqu’à ce que la différence de tour entre les essieux se produise. Il y a des problèmes de chauffage dans des conditions où ils sont allumés et éteints très souvent. De plus, les mécanismes ont une durée de vie, des allumages et extinctions trop fréquents raccourcissent cette durée de vie.

Systèmes différentiels utilisant le mécanisme de freinage du véhicule

Qu’est-ce que l’EDL ? (blocage électronique du différentiel) Systèmes d’assistance à la traction basés sur l’EDL. Nous pouvons inclure tous les systèmes de contrôle de traction électronique dans ce groupe. Chaque marque donne un nom différent aux systèmes basés sur EDL, mais le principe de fonctionnement de base est le suivant. Les véhicules tout-terrain équipés du système d’assistance à la traction du toit EDL sont équipés de capteurs qui comptent les tours sur l’essieu. Ce sont des capteurs ABS. Bien que leur tâche principale soit de servir dans le système de freinage ABS, c’est le fournisseur de données de base de nombreux systèmes tels que EDL, ASR, ESP, etc. Le véhicule détecte la différence de tour sur les essieux droit et gauche grâce à des capteurs ABS. Si la différence est en dehors des tolérances prescrites, il freine automatiquement la roue avec le tour excédentaire. Par conséquent, la puissance du moteur ne s’écoule pas de manière insensée vers la roue de ralenti, mais vers la roue de traction, et le véhicule peut continuer à marcher.. Bien que ce système semble réussi, il n’est pas efficace dans des conditions d’utilisation intensive . C’est comme appuyer sur l’accélérateur tout en appuyant sur le frein en même temps. Cela peut causer des problèmes tels que l’abrasion, l’échauffement, les rayures, etc. sur les disques et les plaquettes. Sans parler de la nouvelle génération, le terrain est situé dans presque toutes les voitures particulières avec des noms différents.

Si nous examinons collectivement la situation des verrous ; Si vous n’avez pas de blocage central ni de blocage de différentiel dans votre véhicule tout-terrain : Votre véhicule est un 4×1 . Si une roue de votre véhicule tout terrain 4×4 perd de l’adhérence, cette roue absorbera toute la puissance du moteur et vous ne pourrez pas conduire votre véhicule .

Si vous avez un Middle Lock mais pas de différentiel : Votre véhicule est un 4×2. Si les deux roues avant ou les deux roues arrière tiennent la route, vous pouvez continuer à rouler. Si l’une des roues avant et arrière (peu importe la gauche ou la droite) perd de l’adhérence en même temps, vous ne pourrez pas continuer à conduire. S’il y a une serrure centrale et une serrure arrière : Votre véhicule est un 4×3. Tant que les deux roues arrière et une roue avant ne perdent pas de traction en même temps, vous pouvez continuer votre balade. Si les deux roues arrière perdent de la traction, toute la puissance passe à l’arbre avant. Si une roue avant perd également de la traction, cette fois toute la puissance va à la roue qui perd de la traction à l’avant. C’est une situation difficile à gérer. S’il y a une serrure centrale et une serrure avant-arrière : Votre véhicule est un 4×4. À moins que les quatre roues ne perdent leur traction, vous n’êtes pas coincé sur la route.

Options de différentiel tout-terrain en fonction de vos préférences que vous devez appliquer afin de modifier le véhicule tout-terrain 4×4, qui a la capacité d’aller n’importe où dans des conditions de terrain difficiles.

Conclusion et suggestions : Il existe de nombreux critères pour le choix de la voiture tout-terrain. À mon avis, le plus déterminant de ces critères est le goût personnel. Par conséquent, il n’y a pas d’arithmétique telle que 2*2=4 pour ce travail. Mon conseil, n’achetez pas un véhicule qui n’a pas de serrure centrale. Si possible, procurez-vous au moins un véhicule qui avait à l’origine un verrou arrière, ou un qui pourrait être verrouillé à l’arrière sans trop de frais. Si vous n’en avez pas, placez la serrure arrière au début des modifications que vous comptez apporter au véhicule que vous avez acheté. Cordialement, Amour.

02.03.2020 Süleyman Atılgan Contact : Facebook & Instagram

Vous pouvez consulter ci-dessous d’autres articles préparés par des professionnels par Süleyman Atılgan, qui incluent des techniques de base tout-terrain et des conseils de conduite tout-terrain.

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Qu’est-ce que le « verrou du milieu » et son importance dans les véhicules tout-terrain ?

Notre sujet aujourd’hui est « Verrouillage intermédiaire hors route »

D’après les commentaires faits à mon article dans lequel j’examinais la relation entre le tout-terrain et le différentiel , je me suis rendu compte qu’il existe une confusion conceptuelle au sujet du blocage intermédiaire du différentiel . Je vais essayer de rendre cette affaire aussi claire que possible.

Les systèmes 4×4 ne sont pas des systèmes qui envoient une puissance égale à tous les pneus simultanément . La puissance du moteur est comme le courant électrique. C’est-à-dire qu’il y a une tendance à s’écouler dans la direction de la moindre résistance. La partie qui produit de la puissance est le moteur , la partie qui la transfère est la transmission , la partie qui la distribue au 1er étage est le carter de transmission tout terrain (boîtier de transfert), l’ accessoire tout -terrain qui la distribue au 2ème étage est les différentiels .

Notons qu’il existe un ordre basé sur la production – le transfert – la distribution . La transmission et les différentiels tout-terrain sont les éléments les plus importants de la marche ou de l’endurance du véhicule.

S’il n’y a pas de facteur limitant pour la division de la puissance à ces points de distribution de puissance, cela déterminera quelle quantité de puissance va de quel côté et quelle quantité de résistance est de quel côté. Ensuite, déterminons d’abord quel est l’élément qui crée la résistance, ce qui répondra aussi à la question de ce qu’est le tout-terrain . Le principal facteur de résistance est la tenue de route du pneu. Si le pneu peut tenir fermement la route, il montrera une résistance élevée. Si le pneu ne peut pas tenir la route, il montrera une faible résistance voire aucune résistance. Ce différentiel absorbera également toute la puissance venant de la boîte de vitesses terrestre à laquelle il est connecté avec l’arbre. Cela signifie que dans un véhicule qui roule sans verrouillage activé, la perte de traction d’une seule roue empêchera le véhicule de se déplacer. Il s’agit d’une situation 4×1 et toute la puissance peut être transférée à une seule roue, et le véhicule ne peut pas marcher car cette roue ne peut pas tenir la route. Afin d’éliminer cette situation, des mécanismes qui limitent la division de la puissance aux points de distribution de puissance ( transmission de terrain et différentiels), que nous appelons “serrures”, ont été développés. « verrou du milieu » fait référence à celui du deuxième étage de distribution de puissance, c’est-à-dire le différentiel “blocage différentiel” Lorsque le verrouillage central est engagé, 50 % de la puissance du moteur sera transférée automatiquement à l’avant et 50 % à l’arrière. Dans ce cas, si les deux roues avant ou les deux roues arrière peuvent assurer la traction, le véhicule pourra continuer à marcher. En d’autres termes, on peut grossièrement appeler cette situation une situation 4×2. Cependant, si chacune des roues avant et arrière perd de la traction, cette fois la roue avant qui perd 50% de toute la puissance qui vient à l’avant, la roue arrière qui perd la totalité des 50 % de la puissance venant à l’arrière absorbera 100 % de la puissance du moteur, elle sera toujours transmise aux roues qui ont perdu de l’adhérence. C’est ce que nous appelons habituellement le crossover. Il se produit rarement sur des pneus du même côté. Lorsque cette situation se produit, le verrouillage arrière sera activé. Lorsque le verrouillage arrière est engagé, chacune des roues arrière partagera à parts égales 25 % de la puissance du moteur. Et si la traction fournie par la roue est suffisante pour entraîner le véhicule, le véhicule marchera. Nous pouvons grossièrement appeler cette situation la situation 4×3.L’étape suivante est lorsque le verrou avant est également activé et que le véhicule est un vrai 4×4. Étant donné que tous les verrous sont engagés, 25 % de la puissance du moteur sera transférée à toutes les roues simultanément. Et si même une roue est en mesure de tenir la route, le véhicule pourra marcher. Nous appelons cette situation à peu près comme un vrai 4×4. La fonction de verrouillage central peut être effectuée en utilisant différentes méthodes d’une marque à l’autre ou d’un modèle à l’autre. Des informations détaillées sont disponibles pour différentes applications sur Internet. Encore une fois, je ferai ma propre classification indépendante de la littérature.

1-) Systèmes de distribution de puissance avec un mécanisme différentiel au milieu : Dans ces systèmes, la puissance est distribuée à l’arbre avant et à l’arbre arrière avec une structure similaire au différentiel classique que nous connaissons. En position ouverte, la puissance est transférée aux arbres avant et arrière, tandis que la rotation différentielle des arbres n’est pas limitée. Lorsqu’elle est verrouillée, cette distribution de puissance s’effectue avec une rotation de l’arbre fixe vers l’avant et l’arrière.Pour autant que je sache, il existe ce type de transmission dans Defender. Voir. Image 1

2-) Les systèmes qui transmettent une puissance constante à la transmission terrestre : Dans ces systèmes, la transmission terrestre est en elle-même ; 2H : Deux roues motrices à grande vitesse4H : Quatre roues motrices à grande vitesse déverrouillées4HLc : Quatre roues motrices à grande vitesse verrouillées 4LLc : Quatre mode roue bloquée. Tous ces modes ne sont pas disponibles sur les transmissions tout terrain. Puisqu’il s’agit de systèmes qui fournissent une distribution et une transmission de puissance entièrement mécaniques, une puissance égale et des tours égaux sont fournis à l’arbre avant et arrière en modes 4HLc et 4LLc. C’est l’une des principales différences entre les véhicules AWD et 4×4. Philosophiquement, je parlerai de la différence entre AWD et 4×4 dans un prochain article. Voir. Image 2,3

Image 2
Image 3

3-) Systèmes de transmission de puissance variable à transmission cross-country : Ces systèmes sont des systèmes qui peuvent faire plus qu’une simple transmission de puissance uniforme avec une logique ouverte ou verrouillée. Ce sont des systèmes qui peuvent décider combien de puissance sera transférée à quel arbre en traitant les informations (ABS, vitesse, angle de braquage, force de traction, taux d’accélération latérale, etc.) Il peut même transférer la quasi-totalité de la puissance provenant du moteur à un seul pneu, avec des systèmes offrant un service similaire dans les différentiels. Ces systèmes sont généralement vus avec des noms différents dans les véhicules AWD plutôt que les vrais 4×4 que nous avons l’habitude de voir sur le terrain. Voir. Image 4.5

  • Image 4
  • Image 5

Tous les modes de traction 2H, 4H, 4HLc, 4LLc que j’ai mentionnés ci-dessus ne sont pas disponibles dans les transmissions tout-terrain. Par exemple, Jeep Cherokee KJ a tous les modes 2H, 4H, 4HLc, 4LLc. (Ce véhicule peut être utilisé 4×2 sur asphalte , 4×4 peut être utilisé à la fois sur asphalte et hors route Jeep Grand Cherokee WJ n’a que des modes 4H, 4LLc. Les modes 4LLc sont disponibles. est qu’il le fait tourner dans différents tours. Ce n’est pas le cas. Dans des conditions routières normales, bien qu’une transmission tout terrain transmette 60 % de la puissance à l’arbre arrière et 40 % à l’arbre avant, les arbres tourneront dans le même tour. Le rapport de la puissance transmise et la quantité de rotation de l’arbre sont des concepts différents . Lorsque le verrou du milieu est activé, la cause de la compression dans les virages du véhicule n’est pas la puissance transférée à l’avant et à l’arrière à un taux différent, mais l’incapacité de répondre aux différentes tendances de tour des pneus en raison du verrou. Cela peut entraîner une usure prématurée voire une casse.Par conséquent, la règle de base est : Le verrouillage central ne doit être activé que dans des conditions tout-terrain et sur des surfaces glissantes.L’un des facteurs pouvant affecter la décision de sélection du véhicule est l’état dans lequel le verrouillage central des véhicules tout-terrain peut être activé. Par exemple, si le verrouillage du milieu ne peut être activé que lorsque le verrouillage du milieu est activé à bas niveau, des insuffisances peuvent survenir dans certaines conditions sur le terrain.Le paramètre le plus important d’une conduite tout-terrain réussie n’est pas seulement le verrouillage du milieu et le différentiel. serrures. Les techniques de conduite en fonction des conditions de piste sont également importantes.Par exemple, sur des pistes où le sol est très glissant avec une transition courte, si la zone glissante n’est pas entrée assez rapidement, le véhicule peut rester malgré tous les verrous. Un véhicule sans verrou peut aller et venir à la vitesse appropriée. Ou, si nous mettons le véhicule sur Low pour activer le verrou du milieu sur une piste où nous pouvons marcher et passer en appuyant sur le gaz, peu importe combien nous appuyons sur le gaz , les pneus ne pourront pas atteindre la vitesse pour nous sortir d’où nous sommes. Conclusion : Un véhicule activable avec la fonction middle lock en 4HLc, c’est-à-dire 4×4 à grande vitesse, sera plus souhaitable sur le terrain.

Meilleures salutations, 03/03/2020 Süleyman AtılganContact : Facebook & Instagram

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Que devrions-nous considérer lors du choix d’un véhicule hors route?

Notre premier sujet est; J’irai à la terre, dois-je faire attention au choix d’un véhicule 4×4 ?

À mon avis, le principal facteur de sélection d’un véhicule hors route est le goût personnel. Le propriétaire est amoureux de son véhicule 4×4 . Si les yeux de l’atterrisseur n’étaient pas aveuglés par cet amour, il n’y aurait pas une telle variété de véhicules tout-terrain . Tout le monde disait « c’est la bonne chose à faire » et un seul véhicule tout-terrain a été convenu et seule cette voiture a été utilisée.

Venons-en maintenant aux facteurs qui affectent une conduite tout-terrain réussie. Chacun de ces facteurs est un problème qui doit être examiné séparément. En fait, je parlerai de chacun d’eux en détail dans le processus en cours. Ici, je ne le mentionnerai que comme sujet principal et donnerai quelques préférences personnelles et opinions générales.

– Système de traction 4×4 :

Le véhicule doit être un 4×4 . Parfois, il y a une envie de sortir sur le terrain avec des cabines doubles 4×2. Alors que les cabines doubles 4×2 suffisamment hautes du sol peuvent servir sur des chemins de terre, il ne faut pas en attendre plus.

Une autre question est 4×4 ou AWD?

Plutôt que les différences techniques entre eux, j’aborderai la différence philosophique entre les deux dans un article plus long. Bien que les utilisateurs des terres aient généralement tendance à utiliser des véhicules 4×4, j’ai en fait constaté lors des voyages auxquels j’ai participé que les véhicules à traction intégrale ont plus de succès que de nombreux 4×4 dans la limite des capacités physiques du véhicule. Cependant, si nous allons faire du tout-terrain, notre préférence devrait être le 4×4.

– Transmission terrestre (boîte de transfert)

Véhicule tout-terrain, en plus d’être un 4×4, doit pouvoir servir avec une transmission terrestre verrouillée ( middle lock ). S’il n’y a pas de verrouillage central, cela signifie que vous commencez le match terrestre avec une défaite 2-0. Bien que cela soit très rare, certains véhicules peuvent ne pas avoir de serrure centrale.

À quoi devons-nous prêter attention lors de la sélection de la transmission tout-terrain ?

Il doit y avoir une option bas régime, que nous appelons Low . Dans la plupart des transmissions tout-terrain, le verrouillage central ne peut pas être activé en mode 4H (haute vitesse 4WD). Pour activer le verrouillage du milieu, vous devez passer en mode 4L (4WD basse vitesse). Peu importe combien vous appuyez sur le gaz en 4L, il peut y avoir des passages plus difficiles ou des trajets infructueux sur certaines pistes, car le véhicule n’est pas aussi agile qu’en 4H. Malheureusement, très peu de véhicules offrent l’option de verrouillage central sur le 4H.

Je le répète, lorsque vous choisissez des véhicules tout-terrain , ne pensez pas aux véhicules qui n’ont pas de serrure centrale.

Off-Road Araçlar da “Orta Kilit” ve Önemi Nedir ?

– Blocages différentiels :
Je ne peux pas dire avec certitude qu’il y a des blocages de différentiel. Parce qu’il n’y a pas beaucoup d’options de véhicules avec des serrures avant et arrière. Si nous disons que c’est tout, nous limiterons les options de sélection de véhicules 4×4 . Cependant, si possible, essayez au moins de choisir un véhicule qui propose le verrouillage arrière en standard. Ou essayez de choisir un outil qui peut être fait plus tard sans le coût et les tracas du verrouillage.

4×4 Off-Road Araçlar da Diferansiyel ne işe yarar ? Diferansiyelin Büyük Önemi Nedir ?

– Sélection de pneus tout-terrain pour les véhicules tout-terrain 4×4
HT-AT-MT-XT me vient à l’esprit lorsqu’il s’agit de pneus tout-terrain . L’aspect que je mentionnerai est la taille des pneus tout-terrain plutôt que le motif.Plus le pneu de votre véhicule tout-terrain est gros, plus votre capacité à surmonter les obstacles avec votre véhicule tout-terrain est grande. De plus , le seul moyen raisonnable d’augmenter la garde au sol de la pastèque différentielle tout-terrain dans les véhicules tout-terrain à essieu rigide est d’utiliser de gros pneus tout-terrain MT ou Extreme . L’utilisation de l’ essieu portique , qui est une autre méthode, est une solution très coûteuse. Essayez de ne pas privilégier les véhicules tout-terrain qui ne permettent pas d’agrandir le pneu à un niveau raisonnable en raison à la fois des contraintes mécaniques et des contraintes physiques dans la zone où se trouve le pneu. Pour qu’un pneu tout-terrain soit agrandi, il ne suffit pas de s’adapter physiquement à l’intérieur du garde-boue. Tous les éléments du groupe motopropulseur du véhicule doivent être suffisamment solides pour résister aux effets accrus dus à la croissance du pneu. Les coupures fréquentes des essieux des véhicules 4×4 avec de gros pneus tout-terrain sont causées par l’ignorance de cela et la croissance des pneus.

Lastik Büyütme ve Offroad Sürüşüne Etkileri Nelerdir ?

– Hauteur :
Véhicule tout terrain. La coupe doit être le plus haut possible du sol. Ne préférez pas les véhicules 4×4 trop près du sol que l’original. Parce que les véhicules tout-terrain n’ont pas une capacité de montée illimitée.

– Angles :
Plus l’angle d’approche – de départ – de neige est élevé, meilleures sont les performances hors route dans différentes conditions. Si le nez du véhicule est trop long, l’angle d’approche sera faible. Nous pouvons citer Toyota Hilux en exemple. C’est la raison pour laquelle certains véhicules tout-terrain laissent un pare-chocs avant lors des déplacements hors route. Examinez bien la structure du pare-chocs avant du véhicule. Pas de plastique qui pende. Sur les véhicules 4×4 à poupe très longue, l’angle de départ est très faible. Presque toutes les camionnettes à double cabine ont ce problème. C’est pourquoi les propriétaires stricts de propriétaires de double cabine coupent et raccourcissent la carrosserie du véhicule. L’angle abdominal est lié à la fois à la hauteur de la coupelle et à l’empattement. Les véhicules à châssis court sont très avantageux à cet égard.

– Système d’essieu et de suspension :
Les véhicules tout-terrain ont généralement des essieux pleins, mais certains ont également IFS (suspension avant indépendante). Presque toutes les cabines doubles sont IFS. Il existe des situations où les deux sont avantageux et désavantageux selon la position de l’obstacle. En général, l’essieu rigide est davantage préféré sur le terrain en raison à la fois de possibilités d’élévation plus élevées et d’une plus grande capacité d’articulation . Soit dit en passant, tous les camions trophées sont à suspension indépendante. Cependant, il y a un écart entre eux et les véhicules tout-terrain 4×4 qui font l’objet de notre discussion.

L’un des problèmes abordés dans le système de suspension est le ressort ou les systèmes à ressort? Choisir un véhicule tout terrain ne permet parfois pas de faire un choix à cet égard. Par exemple, si vous allez opter pour un véhicule double cabine, vous aurez probablement très peu d’options autres que des ciseaux. Mais la tendance générale est aux systèmes ressort + amortisseur plutôt qu’aux véhicules tout terrain à ciseaux. J’aborderai également les systèmes d’amortisseurs, qui sont les instruments de base de l’articulation, dans un long article avec des exemples numériques.

– Capacité d’articulation :
L’exigence de base pour la conduite hors route est que les pneus soient en contact avec la route. Si la capacité d’articulation est faible, le véhicule tombera en diagonale très facilement, et s’il n’y a pas de verrouillage mécanique ou de systèmes de support électroniques qui empêcheront les roues folles d’absorber la puissance du moteur, vous ne pourrez pas avancer. Naturellement, cette capacité est plus grande dans les gros véhicules.

Quel est l’effet de l’articulation sur la maniabilité ? Qu’est-ce qu’une articulation utile ?

Artikülasyon ‘un yol tutuşa etkisi nedir? Faydalı artikülasyon nedir ?

– Empattement :
Lors du choix d’un véhicule 4×4, vous devez faire attention à l’empattement. Être un châssis long ou court a ses propres avantages et inconvénients. Cependant, je n’aime pas les véhicules tout-terrain à châssis court car je privilégie avant tout la sécurité de conduite générale. Les véhicules à châssis court sont plus risqués dans les descentes et les montées raides . D’un autre côté, les châssis longs sont désavantageux, tandis que les véhicules à châssis courts sont très avantageux.

– Largeur de voie :
Plus la distance entre deux pneus d’un même essieu est grande, plus la sécurité du véhicule en dévers est grande. Soyez donc un peu plus prudent sur les véhicules 4×4 très étroits.

– Capacité de bagages :
Le propriétaire a beaucoup de choses. En plus des effets personnels fixes de la voiture, il y aura beaucoup d’articles supplémentaires que vous emporterez avec vous pour le voyage. Les véhicules tout-terrain à châssis court sont très désavantageux à cet égard. Les cabines doubles sont très avantageuses. Cependant, ils paient le prix de cet avantage avec un mauvais angle de distance.

– Moteur – puissance – couple :
Un moteur puissant est généralement mieux. Cependant, si vous conduisez le véhicule à basse vitesse, la puissance du moteur ne devrait pas avoir une grande importance. Ne préférez pas si le véhicule tout-terrain s’entasse même s’il est en circuit bas. La réponse à la question de la puissance ou du couple élevé peut être trouvée dans des centaines d’endroits sur le Web. Permettez-moi de vous donner une brève information, une puissance élevée est requise pour une vitesse de pointe élevée et un 4×4 agile, un couple élevé est requis pour une puissance de traction élevée. Si vous ne conduisez pas en format Rallye hors route, vous devriez privilégier le couple plutôt que la puissance.

– Boite de vitesse :
Il se situe entre les options manuelles et automatiques. La transmission automatique a une longueur d’avance en termes de confort et de facilité de conduite. Mais il a aussi des problèmes. S’il est utilisé pendant une longue période dans des conditions très difficiles, l’huile de transmission surchauffera et vous devrez reposer le véhicule. Vous pouvez également dénuder les plaquettes en mode manuel. Dans certaines conditions, la transmission manuelle peut offrir une conduite plus contrôlée. Ma préférence personnelle est pour les véhicules tout-terrain 4×4 avec transmission automatique.

– Consommation de carburant :
Inutile de dire que c’est bien d’en avoir un rare. Cependant, il ne sera pas possible de brûler même un 4×4 à faible consommation, surtout sur le terrain, et la puissance que nous désirons doit avoir un prix.

– Type de carburant :
Ma préférence personnelle est pour le diesel, mais pas pour une raison très réfléchie. Le diesel est moins dangereux car il n’est pas très inflammable. Si l’essence est laissée à l’air libre, même sa vapeur peut provoquer un incendie. En dehors de cela, le passage de l’eau est plus facile en diesel. Les véhicules tout-terrain à essence sont plus agiles. En général, n’oublions pas que les véhicules 4×4 qui donnent une puissance plus élevée sont à essence, tandis que les véhicules qui donnent un couple plus élevé sont au diesel.

– Fourniture de pièces détachées :
Obtenez des pièces de rechange bon marché si possible. Cependant, la sélection 4×4 ne doit pas être faite simplement parce que la pièce de rechange est bon marché.
Le prix n’a pas de sens si la pièce de rechange est bon marché ou chère, non disponible. Choisissez un véhicule tout-terrain avec des pièces de rechange disponibles. Pensez-y, vous attendez que la pièce vienne de l’étranger depuis 3 mois. Il s’avère également incompatible, vous attendez encore 3 mois. Le véhicule passe la moitié de l’année en position couchée.

– Maître qui comprend :
Si votre véhicule est un véhicule dont la mécanique ou l’électronique sont très inconnues, cela ne devrait pas poser de problème jusqu’à ce qu’un problème survienne. Mais quand vous commencez à avoir des problèmes et que vous ne trouvez pas de solution, vous maudissez la voiture et la vie. Essayez de choisir des véhicules tout-terrain que nos maîtres ont suffisamment de connaissances et d’expérience.

– Coût et âge :
Vous devrez choisir l’une des anciennes options bon marché avec de nombreux échecs ou une nouvelle option coûteuse avec moins d’échecs. Il s’agit bien entendu d’une généralisation. Même s’il est très ancien, un véhicule tout-terrain bien entretenu ne vous dérangera pas. Avant d’acheter un véhicule 4×4, assurez-vous de profiter du service d’évaluation de quelqu’un qui comprend la langue de ce véhicule.

– Expérience :
Respectez les opinions des amis qui ont été canalisés dans un seul véhicule tout-terrain, mais tenez également compte des opinions de nos amis qui ont expérimenté la diversité des véhicules 4×4.

Tous ces sujets principaux sont des sujets qui peuvent être écrits seuls pour de très longs articles. Dans les prochains jours, je continuerai à partager des articles détaillés sur ces deux questions et de nombreux autres sujets.

Cordialement, Amour.

02.03.2020 Süleyman Atılgan Contact : Facebook & Instagram

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Blog Türkiye

What is Pilotage and its importance in Offroad, how is it developed?

Our topic today is “Offroad Piloting” :

You pass, good piloting, you stay bad pilot. So what is this pilotage beyond being a label?

If we are to answer this question with the dictionary meaning; We could answer it as “the job of managing an aircraft”.

As you can see, it wasn’t really about us. However, we will not be confined to the dictionary meaning, but will examine its meaning in our own lives.

Offroad piloting; It is used in the sense of “managing and managing an off-road vehicle”.

Essentially, the conditions for successful driving in offroad are clear. If the tires can provide traction, you can walk, if not, you can’t. So is everything so simple and monotonous?

Of course, it is not so monotonous and simple.

Physical characteristics of the vehicle (ground clearance, tire size pattern width/narrowness, wheelbase, track width, articulation ability), mechanical characteristics of the vehicle (traction system, presence of middle lock, presence of differential locks, engine power, strength of parts in the power flow line) are major factors of successful driving.

Off-road Basic Technical Information

Dear off-road and nature enthusiast friends, we are together with another sharing of our Off-road Basic Technical Information article series. The information I will provide; These are concentrated, technical-based, lived experiences, and some of the details that will find a name in the off-road literature for the first time. With the hope that it will benefit the readers.

Successful piloting; It is the ability to make the right decision without causing any mechanical damage to the vehicle, without weakening the driving safety, which mechanical possibilities of the vehicle should be driven, which track the tires will pass and at what speed the transition will be.

Sometimes you step on the gas and you pass, sometimes taking your foot off the gas allows you to pass. Sometimes you press the tire on such a track that you go on a straight road without feeling anything in the car cabin, sometimes you think you’re going to do a somersault.

pilotage ; It can exist as a skill in humans, but it is also a skill that can be developed by learning and training.

If we explain the situation with concrete examples; imagine a track, a little long. Let’s assume that vehicle handling is not possible in a certain part of the track. If the vehicle does not hold the road, when entering that area, if it is not downhill, that is, if the gravity is not on our side, the vehicle will start to lose speed and will be stuck somewhere. If we give a numerical example; On the track I entered at 10 km/h, in a part of the track where it is difficult to pass, my tires have lost their grip and if my speed drops to 0 km/h before I can pass that area, I will be stuck on the track. Now, on the same track, if I enter the part of the track that does not allow passage at 20 km/h instead of 10 km/h without jeopardizing my driving safety, I can walk normally even if I lose some speed.

Here is successful piloting; It is the ability to decide what my speed should be, taking into account the driving safety in this part of the track.

You can watch an example of this situation in the link .

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I have been doing track training for years, I pass the same tracks over and over with different driving parameters, I observe what happens or does not happen when I try.

I would like to tell a parkour moment. A combination of a deep slit and a steep descent, a descent and ascent where it is crucial to keep the tire on the correct track. While on the descent you only pay attention to where to put the tire on, the situation is more complicated when ascending. At first, I made my exits by engaging all the mechanical possibilities of the vehicle in order not to take risks. Then I tried disabling the front lock first, then I tried disabling the rear lock as well. Then I had stop and go attempts in the middle of the ramp with the 4H middle locked and I was able to get out without any problems. One day, without realizing it, I took a quick walk in 2H, thinking I was in 4H. Then I had unsuccessful attempts at slower speeds in 2H.

You can see this track in the link .

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The result of these trials was as follows; If you enter the track with the momentum needed at the difficult points of many tracks, it is possible to continue your ride successfully. If we consider that we are interpreting the momentum for the same vehicle in the equation P=MxV (mass *velocity), since the mass will be constant, momentum will be the linear parameter of the velocity. So it will change one-to-one with speed.

The faster you enter the difficult points, the easier and more possible it will be to pass there without getting stuck. However, other points to consider here are; must be able to stay within the safety and breaking limits. It should not be accelerated at speeds that would cause the vehicle to topple over or suffer a mechanical breakdown.

In the video given in the link, a crossing from a track entered with the wrong momentum and the correct momentum is seen.

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The transition made after maturing on the same track can be watched from the link below.

These videos are also an explanation of the necessity of training in offroad.

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Being able to evaluate and apply all these parameters correctly can be called good piloting, and on the contrary, bad piloting. Neither good piloting nor bad piloting are concepts that have continuity. In other words, just because you perform well on a track does not mean that you will perform well on every track, even on the same track. The same is true for poor performance.

Conclusion and Suggestions:

– Except for exceptional cases, when we compare two light and heavy vehicles whose values of “(Weight) / (tire floor area)” are close to each other in general, the vehicle with more weight in terms of momentum, that is, with a higher mass, has a higher momentum at the same speed. Since it is high, it can be expected to drive more successfully with more accurate piloting. In other words, you can be expected to drive more successfully with a more understandable language, heavy vehicle and good piloting.

– The different mechanical properties of the vehicles sometimes provide ease of driving, and sometimes they can be a problem for us. In some vehicles, when the front lock is activated, if you turn the steering wheel a little and press the gas, the axle may cut. Or if the axle is strengthened, this time there may be a problem inside the differential. This flow of problems can go in the opposite direction of the engine power flow, to the axle-differential-shaft-terrain transmission-transmission-engine moving parts. These problems can be experienced even in vehicles that are known as international off-road vehicles and are widely used. If we press the gas more than necessary to maintain momentum while using our vehicle, we may break our vehicle. Knowing the mechanical endurance limits of our vehicle is extremely important for both our safety, our pocket and our enjoyment of the work we do.

Let’s not forget that good piloting is first of all not to break your vehicle.

– Although the engine power is a parameter that concerns the final speed of the vehicle, the torque increasing in parallel with the power is our basic need in the field. When a transition is near to occur, the engine can jam even though the vehicle is at low. In this case, piloting or something would be garbage. On the other hand, any vehicle that is considered to have land sufficiency should not have a problem such as gas-eating and piling up, especially when it is under low speed. The conclusion drawn from this is that some vehicles that are considered to be land adequacy are actually not. When choosing our off-road vehicle, let’s be careful about engine power adequacy, stay away from poorly maintained vehicles that will put us in a difficult situation, and take good care of the vehicles we own.

– Every sport requires training, let’s apply this as an unchangeable basic rule for offroad, and try to do training rides whenever possible, even on the same tracks.

Best Regards,

13/05/2020

Süleyman ATILGAN

Contact: Facebook & Instagram

You can view other articles professionally prepared by Süleyman Atılgan, which include off-road basic techniques and off-road driving advice, below.

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What are the effects on the vehicle in terms of roof loads and safe driving?

Our topic today is “What are the effects on the vehicle in terms of ceiling loads and safe driving?” :

A fine analysis that you won’t find anywhere else.

The forces acting on the vehicle can be basically divided into static and dynamic forces. Static conditions are only available when the vehicle is stationary. Due to the fact that the vehicle is in constant motion; We can also call the effects that cause variable loss of balance under different conditions, due to the effects of momentum, centrifugal force, suspension system and rotational effects from the engine to the wheels, and sometimes the braking effect, etc. Since dynamic effects are all mass-related effects, we can think of them as acting from the combined center of gravity of the vehicle.

Combined center of gravity: It is the center of gravity calculated by taking into account all the non-fixed additional equipment, goods and people loads inside the vehicle other than its own weight.

Dear off-road and nature enthusiast friends, we are together with another sharing of our Off-road Basic Technical Information article series. The information I will provide; These are concentrated, technical-based, lived experiences, and some of the details that will find a name in the off-road literature for the first time. With the hope that it will benefit the readers.

Any additional load placed on the vehicle will shift the combined center of gravity of the vehicle upwards if it is placed at a location above the calculated center of gravity of the vehicle when empty. Conversely, the additional load placed below the vehicle’s curb center of gravity shifts the vehicle’s combined center of gravity downwards.

The basic rule of balance-rollover is that the higher the center of gravity is, the easier it will be to roll over, and the lower the center of gravity, the harder it will be.

In order to better understand the subject, it will be useful to read our article where is the balance in offroad and what is its importance .

Denge off-road‘un neresindedir ? Off- Road Araçlar Denge ve önemi nedir ?

Now let’s come to the vehicle specific that will serve as an example for our analysis.

Our vehicle is 190 cm wide from the outside of the tire to the outside of the tire,

Vehicle height is approximately 190 cm,

Our vehicle weight is ~2000 kg,

The additional ceiling test load placed on the vehicle is placed at a height of 200 cm from the ground,

The additional buffer level placed on the vehicle is placed at a height of 70 cm from the ground,

We assumed that the vehicle’s own curb center of gravity was approximately 95 cm above the ground.

ceiling loads; It can form roof tent, roof basket, roof integrated canopy, roof rack, etc.

Buffer level loads are; It can create iron bumper, crane, buffer water tank etc.

In our analysis, we will basically examine the positive and negative effects of an additional 100 kg weight on the vehicle on the bumper or roof position, statically and dynamically.

Positive effect: The effect that helps to stay in balance

Negative effect: The effect that causes the vehicle to lose its balance.

In other words, what would be the difference between the 100 kg weight that we will load additionally to the vehicle at the bumper level and the roof basket level?

According to these answers, we will discuss how we should regulate our driving habits when we put equipment such as roof basket, roof tent, roof shade, roof rack in our vehicle.

For ease of calculation, some measurements have been rounded to more understandable numbers.

The direction of dynamic effects may vary depending on the factor causing the effect. In terms of ease of calculation and the direction in which we think that the moment arm of the effect is at the highest value, we have taken as a basis in our case study.

In addition, since this is an evaluation analysis, assumptions were made in line with the explanations below.

Provided that the F force is the function of the mass constituting the 100 kg weight; will act on the vehicle as a function of momentum, moment of inertia, centrifugal force, braking effect, suspension system, etc. For a 100 kg weight, even though the mass is constant, it may affect the vehicle with different force values at the roof basket level or the bumper level depending on what is caused by the effect. That’s why they are called F1 and F2.

If we enter a curve with a radius of 30 m at a speed of 60 km/h (16,667 m/s);

Centrifugal force to which an object weighing 100 kg will be subjected;

(100 kg) / (9.81 m/s 2 ) * (16,667 m/s) 2 / (30 m) = 94.39 kg. In our example calculation, we can accept this as approximately 100 kg and ignore the situation that the position difference will create and accept F1=F2=100 kg.

Our notation; “+” for all effects trying to stabilize the vehicle and “-” for all effects trying to overturn the vehicle.

While our example vehicle is stationary and level, it will be “+” as it tries to keep both its own weight and additional loads in balance.

While the vehicle weight and additional loads will create a “+” effect when the vehicle is in a flat position and in motion, the force arising from the centrifugal force, for example, will create a “-” effect.

If the “-” dynamic effect that the vehicle is exposed to exceeds the “+” effect that tries to keep the vehicle in balance, the vehicle will roll over.

If we consider that the vehicle is not in a straight position and is leaning to the side in off-road conditions, this rollover may occur at much smaller values of “-“ effects.

Now, let’s do our numerical example for the situation where the vehicle’s center of gravity is inclined enough to align with the outermost point of the tire, which is the tipping point of the vehicle. The assessment will be made only for the additional load.

In this case, the distance of the weight of the vehicle to the vertical axis passing through the tipping point is 0. That is, the force arm of the moment of the vehicle curb weight acting in terms of overturning or balancing is 0 cm. Naturally, if L = 0 in the formula M (moment) = G (weight) x L (arm of force), then M = 0. In this position where the effect of the vehicle weight is 0, the effect of the additional load placed on the roof and bumper level of the vehicle appears as follows;

For static effects only:

For ceiling level loads,

M(-) = 100 kg x (-0.75 m) = -75 kg-m to overturn the vehicle

For buffer level loads,

M(+) = 100 kg x 0.15 m = 15 kg-m to keep the vehicle in balance

If the bumper level and the roof level are on the vehicle simultaneously with an additional 100 kg load,

-75 + 15 = -60 kg-m overturning moment, the vehicle will overturn.

Only if the roof level is an additional 100 kg load on the vehicle, the vehicle will overturn with an excess of -75 kg-m tipping torque.

For static and dynamic effects:

For ceiling level loads,

(As explained above, F1=F2=100 kg is assumed)

M(-) = 100 kg x (-0.75 m) + 100 kg x (-2.10 m) = – 285 kg-m to overturn the vehicle

For buffer level loads,

M(-) = 100 kg x 0.15 m + 100 kg x (-1.15 m) = – 100 kg-m to overturn the vehicle

If the bumper level and the roof level are on the vehicle simultaneously with an additional 100 kg load,

(-285) + (-100) = -385 kg-m overturning moment, the vehicle will overturn.

Only if the roof level is an additional 100 kg load on the vehicle, the vehicle will overturn with an excess of -285 kg-m tipping moment.

As can be seen from the numerical example, additional loads at the ceiling level will cause the vehicle to tip over earlier, both in static condition and under dynamic effects, especially if the vehicle is in a lying position.

While additional loads at the bumper level have a positive effect on the stability of the vehicle in static condition, the dynamic interaction may cause the vehicle to topple even for loads at this level.

Conclusion and Suggestions:

Almost none of us use the vehicles we use in the field in their original form. The most basic modifications to off-road vehicles are vehicle upgrades and tire upgrades. These modifications already shift the center of gravity of the empty state of the vehicle up, bringing a negative situation in terms of balance. In addition to these, any additional load we put on the roof level will cause the vehicle to topple earlier, especially in the side position.

The rider loves his vehicle and loads it with as much equipment as possible. Some of these equipment are visual and some are functional. E.g; inoperative snorkel, inactive dummy radio antenna are some of them. If we accept that we will not be able to drive a raised vehicle with MT – XT tires at high speed, even on asphalt, theoretically, the snorkel, which only negatively affects the vehicle’s aerodynamics, will not have a life-threatening negative effect.

However; Any additional load placed on the roof level adversely affects vehicle safety. So don’t put any really useless heavy equipment on the ceiling level just for the sake of it.

If you need actual use on the vehicle roof; If there is equipment such as baskets, spare wheels, tents, roof racks, awnings, etc., it is vitally important that we drive by being aware of the negative effects of these.

As the vehicle gets higher and/or narrower, or as the 100 kg basket load, which we accept as a reference, increases, the effects will increase negatively.

Best Regards,

22/05/2020

Süleyman ATILGAN

Contact: Facebook & Instagram

You can view other articles professionally prepared by Süleyman Atılgan, which include off-road basic techniques and off-road driving advice, below.

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Steep Climb and Abdominal Angle on Offroad

Our topic for today is “Steep climb and snow angle in Offroad” :

Yes, Dear Friends, this evening we will be doing a technical analysis of a steep climb we made during one of our weekend excursions.

Our first video on the subject is below. They are mostly images of the struggling process.

Our second video belongs to as long as the exit is successful.

There are necessary explanations on the attached pictures.

Note that in the first video, the vehicle had no problem driving up a steep slope, however, once it was suspended, it was no longer able to drive. Even in the most upright position, it can move back and forth briefly. This shows that there is no grip problem on the slope.

Off-road Basic Technical Information

Dear off-road and nature enthusiast friends, we are together with another sharing of our Off-road Basic Technical Information article series. The information I will provide; These are concentrated, technical-based, lived experiences, and some of the details that will find a name in the off-road literature for the first time. With the hope that it will benefit the readers.

The problem arises when the wheels lose traction, when it hangs. If there is no traction on the wheels, tire size, type, compound, middle, rear, front locks, pilotage, etc. are useless. Now, there may be those who think that they can get out of here with a good pilot. Piloting is useless if the tire is not holding the road. Piloting only makes a difference in not falling into that situation. This is a prediction that will develop with experience, when and what to do. In the second video, the output occurs as a combination of both methods. It continues on its way, both the upper corner has been rasped a little and it has reached the inertia that will enable it to pass the moment when the road grip is lost.


When we come to the top corner, because the snow angle is not enough, the chassis is sitting, the tire stays in the air or even if the vehicle is on the chassis, even if the shock absorber stroke is long, after a point, only the axle weight remains on the tire. At such a steep place, the traction that can only be provided under the axle weight is naturally not enough to drive the ~2.5 tons vehicle. The vehicle’s own weight should be transferred to the wheels as much as possible. Coilover shock absorbers will be able to make some difference.

In order to better understand the subject, I will recommend you to read our articulation article.

Artikülasyon ‘un yol tutuşa etkisi nedir? Faydalı artikülasyon nedir ?

It was also possible for me to make the move I made in the second video the first time I entered the track and walk away. However, in this case, there would not be much reason to do the analysis we are doing now, and this would be one of the places we normally walk. So have some fun on the course without risk. This both increases the taste of the work and improves the experience. The goal here is not just to get out. Analyzing the conditions in detail, both to increase experience and to catch the overlooked points and share them with all our friends who are not on the trip.

The track is not a very short track, at least a track longer than the length of the vehicle. This requires us to be very careful at every point. It will be of great benefit to you to read our archive article on steep descent and steep ascent , in which the risks of steep ascents are evaluated.

Araçla dik çıkış mı daha tehlikeli, yoksa dik iniş mi daha tehlikeli ?

The situation I will evaluate here is for the track that we are discussing. The situation is different in the beach-like straight driving track.
Avoid bouncing the vehicle too much. Especially on hard ground when the locks are not engaged and at high RPM.
As soon as the front tires of the vehicle are inflated, if the middle lock is not engaged or one of the rear wheels loses traction even if the middle lock is engaged, both of the front wheels or, since the moment of separation from the ground is different, one of the front wheels will be able to absorb all the power of the engine. If the vehicle is not 4L but 4H, this time, the speed of the front wheels will increase. We do not have a habit of braking when the vehicle is airborne, we continue to press the gas. This is a factor that will increase the rotational speed of the tire, not the speed of the vehicle. Also, if the front wheels fall on a ground with good grip after jumping, you may cut the axle or cause damage to the differential (such as stripping or breaking of the axle gears or spider gears, breakage of the axle shaft of the idler gears, breakage of the gear housing, etc.). (For example, if you are jumping from the steep dirt exit on the side of the road to the asphalt, and you can not increase the speed of the vehicle, this exit is loaded on the gas and you increase the speed of only the front wheels.)

The lower the speed of rotation of the rear tires of the vehicle and the speed of the vehicle itself, the higher the rotational speed of the front wheels, and after the front wheels reach this high speed, the torsion effect on the axles occurs due to both the low speed of the vehicle and the ground not allowing the tire to rotate. won’t be able to and will cut it. The differential side of the axle will try to turn, while the tire side will try to stop abruptly when it touches the ground.
In 4L, the situation is a little different. In general, in 4L vehicles, the middle lock is also activated. This will eliminate the speed difference between the front shaft and the rear shaft. However, when the front wheels are lifted into the air, if the rear wheels also slip and increase their speed due to both the general jumping tendency of the vehicle and the slippery ground conditions, this time when the front wheels touch the ground, the axle may cut again due to the higher transmission power of 4L, even if the speed is not very high.

In addition, the structure of the track can change after each pass, sometimes the vehicle driving in front makes the road, sometimes it breaks it. The channel formed while trying to make a trace in the video is filled and the corner is a little rasped and disappears and the risk of sitting on the stomach of the vehicle is reduced.

Conclusion and Suggestions:

Always be careful in the field, don’t drive loosely. You may not have noticed at the beginning how dangerous the track is, be alert at all times, and have an assistant guiding you if possible.

If the sudden change in load on the axle has an effect on the axle’s capacity, the axle cuts off. It is necessary to understand how this effect occurs and to avoid those movements.

Do not bounce the vehicle. While jumping may seem like fun, it’s probably the most damaging mode of use to the vehicle’s drivetrain. Be even more careful in this regard, especially on vehicles that have not been modified with stronger parts.

Best Regards,

13/05/2020

Süleyman ATILGAN

Contact: Facebook & Instagram

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How to Overcome the Obstacle in Offroad?

Our topic today is “How to Overcome the Obstacle with an Off Road Vehicle? “

We will look for answers to the questions of what to do when crossing rough terrain with your 4×4 off road vehicle or on short but steep and high ascents, what we can do, what are the situations in which we cannot get out, what are the dangers.

First of all, it is assumed that the height difference between the planes we are on and the planes we are trying to climb is not so much that the corner of the ramp or the obstacle we are trying to overcome is not enough to suspend the vehicle from the chassis when the rear wheels of the vehicle rest on the ramp. If the chassis touches the ramp to be climbed, it will be possible to climb to the extent permitted by the simultaneous articulation capability of the tires on the same axle.

Let’s examine how climbing is possible in a basic sense.

Dear off-road and nature enthusiast friends, we are together with another sharing of our Off-road Basic Technical Information article series. The information I will provide; These are concentrated, technical-based, lived experiences, and some of the details that will find a name in the off-road literature for the first time. With the hope that it will benefit the readers.

If more than one tire simultaneously leans against an obstacle, it may not be possible to continue driving, depending on the geometry of the obstacle and the grip of the tires. Therefore, it must be ensured that more than one tire does not hit an obstacle simultaneously. These; It can be two front tires, two rear tires, or one front and one rear tire. If more than two tires are leaning against the obstacle, the transition will become more difficult.

Even if the tires resist simultaneous obstacles, it can be reached and passed at a certain speed.

However, you cannot quickly cross obstacles that exceed the height corresponding to the positions of the tire’s angle with the vertical exceeding 75 degrees.

Since they stand like a flat wall in front of the tire, when we make a move to come and pass quickly, it will create a direct impact to the vehicle and the vehicle will be exposed to the same situation as in a normal collision accident and it may break or there may be permanent bending and twisting of the front wheels.

In this case, the larger the tire, the more successful the transition will be.

I recommend you to read our article about the effects of tire growth on offroad driving.

Lastik Büyütme ve Offroad Sürüşüne Etkileri Nelerdir ?

If the tires have managed to climb the obstacle in front of them, they will likely be in a typical crossover situation. In this case, the vehicle’s articulation capability and/or the availability of differential locks will be key factors in continuing driving.

In order to better understand the effects of articulation ability, I would recommend you to read our article on the effects of articulation ability on offroad ability.

What is the effect of articulation on handling? What is useful articulation?

Artikülasyon ‘un yol tutuşa etkisi nedir? Faydalı artikülasyon nedir ?

`

Similarly, in order to better understand the effects of differential locks on road holding, I recommend you to read our article in which the differential is explained in detail.

`

4×4 Off-Road Araçlar da Diferansiyel ne işe yarar ? Diferansiyelin Büyük Önemi Nedir ?

Because obstacle-crossing or a short steep climb are very similar in essence, you might consider our interpretations of the steep climb similarly when surmounting mixed obstacles.

If we approach the obstacle in the P1A position, if the obstacle is too steep, the obstacle will stand like a high wedge in front of the two front wheels and it may not be possible to move the vehicle up. Even if the front wheels are able to overcome this obstacle with the rotational motion and the thrust of the rear wheels, this time in the P3A position, the rear wheels will stick to the ramp like chocks.

The correct approach position is therefore P1B, P2B and P3B, where the tires cross the obstacle one by one. It would be more accurate to enter at a slight angle and let the wheels come out one by one. However, this position will also require the vehicle to have articulation capability for successful ascent. It will be a very enjoyable and successful experience for a vehicle with high articulation capability and differential locks.

The dangerous situation is P1C, P2C and P3C. If we give the angle a little too much, if we press the gas straight, and if there is enough ramp height, we can overturn the vehicle before we reach the P3C position.

In this and similar positions, the risk of tipping over is examined, “Where is the balance in off-road and what is its importance ?” I recommend you to read our article.

Denge off-road‘un neresindedir ? Off- Road Araçlar Denge ve önemi nedir ?

Now let’s move on to the other successful exit parameter. In order to make this output, the middle lock must be present. In position 2, the rear wheels must be on a stable surface. In position 3, the front wheels must be on a roadworthy surface. If you cannot meet these conditions, you are tiring the vehicle for nothing.

In the attempt to exit the stream bed seen in the photo, it would be a pointless behavior to push this track further, as the rear wheels were buried in the bottom of the stream bed and road holding became impossible. With more qualified tires, even on that ground, road grip can be achieved and exit can be achieved. However, the result is still tied in position 2 whether the rear tires hold the road or not. Since the road holding could not be provided under the conditions we were in, we acted prudently and did not continue the struggle despite all the encouragements (fillings) of our friends who participated in our trip.

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I recommend watching the video of the climbing attempt, where the photo was taken.

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Conclusion and Suggestions:

Do not be tempted by the video footage of vehicles equipped with over-modified, large XT tires and coilover shock absorbers on difficult tracks. Know the tool you have, give yourself time about what you can do, what you can’t do, what you should not do, and proceed by gradually increasing the dosage each time. Just like every activity requires training, offroad is an activity that requires training. Do a lot of training, even having these trainings on the same track will make positive contributions to you. After years of using all the mechanical possibilities of my vehicle on a short track with loose surfaces, longitudinal slits, quite steep and with a “slit” on one side, one day, absentmindedly, I walked a little fast in 4×2 mode. There’s no end to the experience you’ll get, it’s just that you learn more and more new information at the beginning, and as time goes on, what you learn will never end as you learn more. Try to do every ride with a certain look and mind. Be sure to examine the place you are going to pass, where should I drive the tire, wherever I hit the differential watermelon, where the ground provides the best traction for the tire, where do I put myself in the least danger, on which track should I run the car the least, at what speed should I make this transition, my vehicle’s traction system and articulation Always keep in mind questions such as whether its ability is suitable for this transition. Driving with these questions will provide you with a vision in which you can open your own track after a while. The offroad community is huge and continues to grow day by day. We have come to see the majestic cars, which we have rarely seen in the past years, more often. There is no such thing as the best offroad vehicle, our goal should be to equip the vehicle we have with the right equipment and get the highest efficiency from it.

Let me put it in the last word, do not buy a vehicle without a middle lock, if possible, choose a vehicle that has a minimum rear lock or can be installed without much expense.

Normally ; Keep in mind that the middle lock + rear lock + MT Tire combination will outperform the middle lock + XT Tire.

Best Regards,

25/03/2020 Süleyman ATILGAN Contact: Facebook & Instagram

You can view other articles professionally prepared by Süleyman Atılgan, which include off-road basic techniques and off-road driving advice, below.

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Which tire should I choose in the field?

Off Road Tire Selection

Today’s topic is “Which Tire Should I Prefer On The Field?” :

The tire business is a complete mystery, especially for newcomers to the offroad community. After some time passes and gaining enough experience, everyone will follow a truth in their own way. These truths will often differ from each other. I will also try to share my own experiences and observations.

First of all, let’s start by reminding the types of offroad tires we use on vehicles.

AT – All Terrain

MT – Mud Terrain (in mud lands)

XT – eXtreme Terrain (Extreme / extreme terrains)

We can say that there is a general classification of offroad tires called.

When you search for offroad tires on the internet, especially in most of the sales sites, you will see the following numbers when choosing a tire;

50% Asphalt – 50% terrain AT Tire,

20% Asphalt – 80% land, MT Tires,

5% Asphalt – 95% terrain XT Tire.

Especially the new offrod driver can dive into the AT tire so that my car can go everywhere, choose MT tires due to the definition of “mud terrain”, or get XT tires so that I can be the best. If he has the chance, the general purpose and usage style fits the tire he chooses and he continues to use it without any problems.

First of all, it is necessary to start with the correct understanding of what the percentages given above mean. These percentages are related to how long the vehicle to which the tire will be mounted spends on approximately average asphalt and terrain conditions. It has nothing to do with asphalt driving comfort or off-road driving success.

Asphalt conditions are certain, but land conditions are very variable. The dirt roads in the forest are also considered land, the mud you enter up to your waist.

Therefore, we must choose a correct target for ourselves and determine our tire type in line with that target.

I will try to explain some targets and the tire selections made to reach these targets and the results with examples.

Goal : I will go to the field, but I want a smooth ride on asphalt.

Preference: AT Tires will be preferred.

Result : The expectation of a comfortable ride on asphalt is met. If your expectation from off-road driving is dirt road trips, you will be satisfied on the field as well. Unfortunately, your heart breaks a little in offroad driving with more difficult loose, muddy, wet steep ascents and descents. In the snow, you will be flattered this time when you perform higher than the MT’s, which are thought to be more land-racing.

Goal: I want an above-average driving success even in challenging conditions.

Preference: MT Tires will be preferred.

Result : You will feel a slight click on asphalt at speeds below 20 km/h, and you will hear an intense hum from the road at speeds above 80 km/h. In addition, you will no longer be able to reach the speeds you can reach with asphalt tires on the vehicle for driving safety. While your performance on loose ground, rock ground, and steep descents and ascents will be at the level you desire, you will find that contrary to its name, it is not so successful in mud. You will be nervous when you start to realize that you are slipping on asphalt in the rain. In the snow, you will be a little twisted when you fail more than the AT’s, which are considered to have lower terrain capability.

Goal : I want unconditional success in every track on the field. (There is no such thing as unconditional success in the field, but let’s say this is our goal)

Preference: XT Tire will be preferred.

Result : Desired success will be achieved especially in mud tracks. However, if possible, have the track somewhere in the backyard of your house. You will have a lot of blessings on the father of the XT tire when you go 60-70 km, make a maximum of 10 km in the field and come back 60-70 km again. In asphalt driving, rattling and humming will not be missing at any speed level.

Goal : I am looking for a successful ride on every track and a high level of comfort on asphalt.

Preference : ???

Conclusion: There is no tire of the type that will allow us to achieve this goal. There are statements that MT asphalt driving comfort and XT off-road performance can be obtained only for some tires. Let me pronounce one of them, Interco Super Swamper TSL SX.

Even between tires of the same category, there can be significant grip differences. These determinations were made by considering the general tire characteristics. While the performance of MT Tires in snow driving is not stable, the snow performance of a certain brand of MT tire can also be exceptionally high. In this case, we will say that exceptions do not break the rule.

I recommend you to read our previous article about snow driving.

Karda araç kullanma ve yol tutuş

When driving an off-road vehicle, successful off-road driving can sometimes get in the way of everything. In fact, this is a bit of a person’s self-defeat. Please don’t be tempted in the field, and don’t wear sergeant pattern-shaped tires that don’t suit off-road vehicles, just because I’m going to pass through here. It is a tire that does not suit an all-terrain vehicle. They’re not construction machines, they’re all-terrain vehicles. Get a 4×4 tractor or JCB 4CX and if the goal is just a successful drive, you will be much more satisfied.

Conclusion and Suggestions:

When choosing tires, be aware that the discourse AT if 50% Asphalt – 50% terrain, 20% asphalt – 80% terrain MT, 5% asphalt – 95% terrain XT is a hoax and is not directly related to off-road driving success .

When I got my first all-terrain vehicle, the first thing I did was change my tires. I fell for this % error too. I bought a set of AT tires. I didn’t even feel the need to change the spare wheel. My psychology was like this, “I go anywhere, do anything”. Disappointments over time kept my feet on the ground.

Be clear about your expectations before choosing a tire. If possible, test drive a vehicle equipped with the tire type you are aiming for, both on asphalt and off-road so that you do not encounter any surprises later.

The tire set is not 4 pieces, but 5 pieces. Make sure to include your spare tire in the kit.

For off-road vehicles, different tire sets can be installed for summer and winter seasons. E.g; AT in summer MT in winter or MT in summer XT in winter. Considering the economic conditions of our country, this is not possible.

I go one step further and say that a landlord needs 4 vehicles. One that he will use for camping (let’s get this defender) without going on very difficult tracks, one double cabin where he won’t have to worry about where to put my belongings, one that he can use as a hobby car (if possible, get a rubicon), and one that he can use excessively and hurt himself.

By the way, snow tires, which are not in the category of off-road tires, but with surprisingly good off-road performance, created wonders with Kanaga Smyrni and Volkan Dural Subaru, which we went on trips with last year.

Let me put it in the last word , do not buy a vehicle without a middle lock, if possible, choose a vehicle that has a minimum rear lock or can be installed without much expense.

Normally ; Keep in mind that the middle lock + rear lock + MT Tire combination will outperform the middle lock + XT Tire.

Best Regards,

23/03/2020 Süleyman ATILGAN Contact: Facebook & Instagram

You can view other articles professionally prepared by Süleyman Atılgan, which include off-road basic techniques and off-road driving advice, below.

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Heavy Vehicle or Light Vehicle in Offroad?

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Off-road Basic Technical Information

Dear off-road and nature enthusiast friends, we are together with another sharing of our Off-road Basic Technical Information article series. The information I will provide; These are concentrated, technical-based, lived experiences, and some of the details that will find a name in the off-road literature for the first time. With the hope that it will benefit the readers.

Our topic today is “Heavy Vehicle or Light Vehicle in Offroad?” :

Our question is actually whether a heavy vehicle or a light vehicle should be preferred on the axis of successful offroad driving, but the weight will be evaluated parallel to the size of the vehicle and shifted to the axis of large, vehicle or small vehicle.

I will try to evaluate the road holding point, which is the basic element of a successful offroad driving, without causing too much axis shift.

track ; mud, loose dry ground, snow, sand, rock.

The essence of the problem is not which vehicle we use more efficiently within the framework of picnics, camping and other outdoor activities, but which vehicle we get more efficiency from directly offroad.

For successful offroad driving, the answer to the question of whether it is a heavy vehicle or a light vehicle lies in the basic laws of physics.

The force that makes the vehicles move is the force that occurs between the wheel and the ground on which it walks. We call it traction. Wikipedia definition; (traction or traction force) is the force used to produce motion between a surface and a tangential surface through the use of dry friction.

There are many parameters that affect this force. Ground quality, rubber compound, tire pattern, tire width etc. are the most important of these.

Therefore, in order to make the evaluation under correct and equal conditions, all of the vehicles started to slide at 45 degrees inclination in the inclined plane test, that is, the static friction coefficient.

We will assume that µ = tan 45 = 1.

To simplify the situation, I will not distinguish between static and kinematic coefficients of friction.

There is an upper limit to the resulting traction force between the tire and the surface. The higher this limit is, the better the vehicle will handle, the lower it is, the worse it will handle.

Here, we call the value that creates this upper limit of the traction force “F_s, friction force”.

The frictional force is equal to the perpendicular force between the two surfaces times the coefficient of friction.

F_s = N x µ

Since we assume µ=1 in this equation, the friction force is a linear function of the normal force N. The result here is indisputable and very clear. In cases where frictional motion is provided, the higher the vehicle weight, the higher the handling. The higher the grip, the higher the offroad driving success .

So, is this situation as many times as 4×4 = 16?

This is offroad, nothing can be that precise of course.

Now let’s consider other situations that affect it.

Walking on the ground happens in two basic ways; the first by floating on the ground, the second by clinging to the ground.

Progress by floating on the ground; in sand, sometimes in snow, very rarely in mud.

Progress by holding on to the ground; It happens on loose dry ground, rock ground, sometimes snow, often when hard ground can be reached at the bottom of the mud.

If the vehicle is floating on the ground, if the vehicle weight increases, the vehicle will sink, that is, the differentials and / or the chassis will sit and the vehicle cannot continue on the road. Here the situation is balanced by using large and wide tires on heavy vehicles.

If it is advancing by holding onto the ground, the heavier the vehicle, the better the handling.

Other considerations for weighted or already heavy vehicles:

– Engine with enough power for the weight of the vehicle is required

– Fuel consumption of heavy vehicles is always higher.

– Axles, differentials, shafts, cross-country gearboxes and gearboxes are required to be robust enough to meet the weight of the vehicle.

– It should be noted that the mass moment of inertia of the heavy vehicle will be more difficult to overcome and the acceleration performance will be low. That’s why rally drivers, whom I describe as “dirt road gassers”, always prefer vehicles that are as light as possible and gain the greatest advantage in races by reaching the highest speed as soon as possible after their speed drops. This is only possible with a light vehicle. Since we evaluate offroad driving, not time-trial competitions, our preference should be heavy vehicles.

Please remember the video he took of all the vehicles attached to the back of the Lada Niva, of which there were about 10 men.

The information I give is for situations that are expected to happen in the majority. Situations that occur outside of this are also different situations that can arise under their own conditions within the framework of the physics rules I have defined. But the laws of physics are absolute and cannot be changed, at least within the framework of current knowledge.

As we said, 4×4=16 doesn’t happen all the time. Despite all the equipment, Niva can sometimes pass where other vehicles cannot pass. Sometimes, a heavy and bulky Toyota can pass by where the Niva floundered.

Yes, where the heavy vehicle cannot go, the niva may have walked away. It is a ground where it is not possible to cross the loose ground and find the hard ground without the vehicle sitting on the base. If the vehicle floats on the loose ground, it will only be able to pass the track. A light and wide wheeled Niva has walked away where the heavy vehicle is buried up to the chassis. Well, in what % of mud tracks this is the case. It’s not even 10% that I’ve experienced so far. So then it would be more accurate to comment according to the 90% part. This is how I come to the conclusion that a vehicle with a large tire diameter and a suitable pattern, which can generally reach and hold the hard floor on the mud, makes a more successful ride. Is there no exception, yes, there is the niva we gave an example above.

Or let me give you the opposite example, a heavy vehicle in the sand is considered as trouble. Whereas, a vehicle with heavy but wide tires will probably be more successful in driving while maintaining its momentum, than a vehicle with light but very narrow tires. What happened, the light vehicle sank, the heavy vehicle passed. Even so, the main thing is that the laws of physics work according to the vehicle and track conditions for the moment.

Conclusion and Suggestions:

As I mentioned above, provided that the parameters affecting the friction coefficient are equalized, the friction force, which is the upper limit of the traction force of heavy vehicles, will be higher, so it is expected to drive more successfully in the offroad with at least 80% accuracy. The exceptions that we call the opposite situation do not break this rule, they have already produced their own results in a different way within the framework of the same physics rules.

It is expected that a vehicle with a wheelbase between 100”-120”, around 2000 kg in its equipped state, with suitable approach and departure angles, will have a higher off-road performance than other vehicles with the right tire choice.

Even though the big brothers appearing in the field with their weight based on the 3000 kg limit, 39”-42” big tires and fuel tanks up to 200 liters dazzle you in the videos, when considered as a whole, they are not very acceptable vehicles for us ordinary offroaders .

Despite its small size, it should not be overlooked that vehicles that are heavier than normal may experience breakage problems in the driveline.

Let me put it in the last word , do not buy a vehicle without a middle lock, if possible, choose a vehicle that has a minimum rear lock or can be installed without much expense.

Best Regards,
18/03/2020
Süleyman ATILGAN
Contact: Facebook & Instagram


 

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What are the Effects of Tire Growth and Offroad Driving?

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Off-road Basic Technical Information
Dear off-road and nature enthusiast friends, we are together with another sharing of our Off-road Basic Technical Information article series. The information I will provide; These are concentrated, technical-based, lived experiences, and some of the details that will find a name in the off-road literature for the first time. With the hope that it will benefit the readers.
Our topic today is “ What are the Effects of Tire Growing and Offroad Driving? ” :
We can think of the first step of vehicle modification as changing tires. If we have not bought a ready-made vehicle, if we have bought a standard vehicle, the first thing we will do is to change the tire.
First of all, let’s take a brief look at the tires we use in the field. AT (All Terrain), MT (Mud Terrain), XT (Extreme Tarrain) Since this article is not about tires, it’s only about tire enlargement, I won’t go into extraneous details.
Which type of off-road tire should I choose? The answer to the question is in our article in the link.
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I want to enlarge my tires, how much should I enlarge and why should the tire be enlarged in the field , let’s try to find the answers together.
Large tires have greater obstacle clearance than smaller tires. So as the tire gets bigger, your ability to pass over the obstacle will increase. If we examine the attached picture, it can be seen that the heights that the tire can exceed at the same angle position are different in different diameter tires and, as the tire diameter increases, the height corresponding to the same angle also increases. If we examine the values in the table, we can see what level this increase is. To give a numerical example, at a fixed angle of 75º, which will create the same difficulty for the tire, a 27″ tire can overcome a 25.4 cm obstacle, while a 35″ tire can overcome a 32.9 cm obstacle. When we look at it in centimeters, this difference, which seems small, is 30%. When we go to 37”, the difference will be 38%. That is, an obstacle that is insurmountable for the small tire, such as a flat wall, will be an obstacle that can be climbed and rolled over for the large tire.
The net result here is that the bigger tire is always more capable in terms of off-road ability.
Tire diameter and tire width should not be confused with each other. The two are very different concepts in terms of benefit/harm, depending on the background. But for commercially available tires, in general, the larger the tire diameter, the larger the width.
Especially in solid axle vehicles, there is no “reasonable” way to move the differential watermelon off the ground, other than to increase the tire diameter. Portal axis-like applications are utopian solutions for the vehicles we are talking about.
Assuming that the differential watermelon of a normal vehicle is ~ 16 cm from the ground, for a vehicle with an increased tire size of 3” (eg from 30” to 33”);
3 inches x 2.54 cm/inch = 7.62 cm
7.62/2=3.81cm
3.81/16= 23.81% is a considerable increase.
Sometimes you need 1 cm to move forward without hitting the bottom of the vehicle. If you have that 1cm you will pass without hitting, otherwise you will hit pass or you will fail.
It is an indisputable fact that for successful off-road driving, it is necessary to make our tires as large as possible.
What could be the limiting factors for tire growth?
If we examine these elements under the headings:
Physical Limits:
The tire must physically fit inside the hood and fender. Or this should be achieved with minor shaving. You can make bigfoot with very deep modifications, there is no limit here. Our assessments are for modifications to be made within reasonable limits.
If the upgrade kit is applied, I recommend doing this without going too far.
Does being able to physically place the tire inside the hood or cut it a little bit will allow us to enlarge the size as much as we want? For example, can we put 42” tires on the jimny?
There is no obstacle to wearing, the important thing is can it be used healthily? Especially in Istanbul groups, it is possible to come across Suzukis fitted with sergeant pattern large tires. It is useful to look at these vehicles and know that these tires are not mounted by simply shaving the hood and fender. Many of them are vehicles with profound modifications to the drivetrain.
Limiting Factors Regarding Drivetrain:
On the one hand, while growing the tire, on the other hand, it is necessary to ensure that the power of the vehicle flowing over the engine-transmission-road transmission-shafts-differential-axles is transferred to the tires without forcing the vehicle to break.
If we change the final drive ratio as we enlarge the tire relative to the original, we will reasonably reduce the risks for the system up to the differential. This means: If we increase the tires of a vehicle with final bevel ratio 4.10 and original tire 32” to 35”, the new ratio will be 4.10*35/32 =4.48. That is, the new final final ratio must be greater than 4.48 and the closest ratio. It could be 4.56 for example. After this change is made, the additional forceful effect created by enlarging the tire will be eliminated in terms of engine components-gearbox-road transmission-shafts. However, this will not be the case for the inside of the differential and the axles. If the inner casing of the differential, idler gears and shafts, axle gears and axles, U-joint or CV-joint connections at the front do not have the strength to meet the increased load, if you do not drive the car very naively, it will say “checkerboard” somewhere and break.
In accordance with the impulse-reaction principle, a force equal to the force exerted by the tires on the ground to propel the vehicle is applied by the ground to the outer wall of the tire. In other words, as the tire diameter increases, the moment arm of this force will also increase, so the vehicle will need more power with the growing tire and will be forced more.
The upper limit of the force transmitted to the axles will cause a torsional moment equal to the friction force * the radius of the wheel. Since the radius is a factor in the equation, the larger the diameter, the greater the opposing torsional moment. If we’ve made the tire too large for the vehicle’s infrastructure to handle, this opposing torsional moment can cut the axle. If the axle is strong enough, the differential can fall apart, and if it is strong enough, it will break whatever it finds weak, such as the shaft cross, the gearbox, the gearbox, the engine. If it breaks none, the vehicle’s infrastructure is already strong enough to handle that size.
This is not the only parameter that forces the tool. To a lesser extent, there is also the mass moment of inertia of the tire, which is a parameter of the tire’s mass, which opposes the power from the engine during starting. It is the counter-mass resistance that occurs when we try to move the tire at rest. Since the mass is obtained by dividing the weight by the gravitational acceleration and the gravitational acceleration is constant, we can also evaluate the change in the moment of inertia directly as a parameter of the weight.
In other words, the mass of the tire is directly proportional to the moment of inertia, its weight and the square of its diameter. (I=mr^2/2)
This resistance will increase as the tire gets heavier and its diameter increases.
This means that ; After the tire has grown, do not press the gas too hard, you will cut the axle. This situation is very common in ZJ and WJ group vehicles with DANA 30 Front differential.
That’s why, with the drivetrain unmodified, the persistence of continuing to drive that “majestic” defender with tiny tyres.
Other Elements:
Your vehicle, which you have modified by installing large off-road tires, is now; It has become a vehicle that consumes more fuel, the road grip on asphalt is weakened, the speed limits have been reduced significantly for safe use, and it has become a vehicle that strays more than its track even in bends on asphalt. If you want to be affected by these factors at the lowest level, it is useful to know that you have to make your tire less big.
Conclusion and recommendations:
As all landlords know, as a vehicle approaches the terrain, it moves away from the asphalt. If I have asphalt performance and safety, and my off-road performance is very high, I feel like I’m full and I have a cake. There is no such option.
Generally, we can say that the bigger the tire, the better off-road performance.
If you’re going off-road, upgrade as much as the vehicle’s infrastructure allows and fit the largest tire.
Grow your tires, but don’t make the decision about how big you want to make just on the basis of your ability to physically fit the tire to the vehicle. Enlarge your tires by modifying these transmission parts, if necessary, within the tolerances of the vehicle’s existing drivetrain systems.
The key word is “the vehicle’s infrastructure allows”.
Large tires also affect the vehicle image very positively. However, I do not think that our friends who are actively on the field grow tires just for the vehicle image.
When you increase the tire, press the gas a little more moderately, avoid sudden loads. Knowing that throttle reaction devices increase the level of spikes, avoid using devices that reduce throttle reaction times, especially on vehicles with oversized tires to the vehicle mechanical limits.
Do not ignore the general recognition that non-rubbing tire sizes of vehicles in moderately elevated states are also the manufacturer’s maximum sizes that can be used in drivetrains without additional action.
Changing the tire size and/or final drive will cause deviations between the actual speed of the vehicle and the gauge speed. While corrections can be made with software dexterity in new generation vehicles, this problem can be eliminated in old generation vehicles by changing the speed wire gear corresponding to the tire size and final drive ratio. The arrangement made with software dexterity not only corrects the speed, but also regulates the gear shift revolutions according to the new situation, if the vehicle is an automatic transmission.
Large tires used for offroad purposes are generally wider as well. If the vehicle has the original tire 245mm wide and mounted on a 7″ wide rim, you will likely need new 9″ offset wheels if you have increased the tire to 35″x12.5″. In the data sheets of the tires, there is information about the min-max rim widths that they can be fitted. Do not rely too much on the information of the sellers, get the information about the recommended rim width of the tire you choose directly from the manufacturer’s site.
Even if you don’t have a problem with flat road driving with enlarged tires, there is a possibility that you may have problems with articulation and/or hood rubbing at full turn of the steering wheel or rubbing directly against the chassis or bodywork. This situation may also differ according to tire brands and types. Sometimes even the lift kit application may be insufficient. Try it out if possible.
Best Regards,
16/03/2020
Süleyman ATILGAN
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Contact: Facebook & Instagram

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What is the effect of articulation on handling? What is useful articulation?

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Off-road Basic Technical Information
Dear off-road and nature enthusiast friends, we are together with another sharing of our Off-road Basic Technical Information article series. The information I will provide; These are concentrated, technical-based, lived experiences, and some of the details that will find a name in the off-road literature for the first time. With the hope that it will benefit the readers.
Our topic today “What is the effect of articulation on handling? What is useful articulation?”:
Our topic is articulation, and a fine analysis that you won’t find anywhere else.
Let’s start with the basic definitions. You can find the definitions of articulation in the literature when you google it. Our friends who follow me know that I have made definitions and determinations independent of the literature in my articles. This time, I will describe it in the same way as I understand it from my own perspective.
Articulation capability is the ability of the wheel to move away from or approach the vehicle’s coupe. The greater this difference, the greater the articulation ability. We can call moving away positive articulation and approaching negative articulation . In general, positive articulation is more and negative articulation is less.
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The answer to the question of why articulation is necessary will appear at the end of our article.
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Let’s start from the very beginning, “the world was a cloud of gas and dust”.
The main force that makes vehicles move is the traction between the wheels and the ground. Traction is essentially a medical term. However, we will use it as we understand it. It is the traction force that occurs between the tire and the road and enables the vehicle to walk.
The more this force is, the better the tire can handle, and the better the tire can handle, the more successfully the vehicle can move forward. Whether this force is large or small; It depends on many parameters such as tire paste, pattern, width of the tread, tire air, the character of the ground on which one tries to move, etc.
Considering all these parameters, let’s assume that there is an “average coefficient of friction ” between the tire and the ground. The maximum value that the traction mentioned above can reach is the friction force between the tire and the ground. This frictional force is equal to the product of the average friction coefficient between the tire and the ground, which we mentioned above, and the normal force between the two surfaces, that is, the load transferred to the tread.
F_s = µ * N
There are two types of friction coefficient, static and kinematic . The static friction coefficient is the value before the slip starts, while the kinematic friction coefficient is the value after the slip starts between the surfaces. They can be easily determined by the inclined plane test . Since the kinematic friction coefficient has a lower value, the friction force, which is the upper limit of the traction force, will take a lower value after the skid starts.
In practice, it is sometimes possible to drive the car with increased skid. This is due to the fact that the interaction between the tire and the surface is not a uniform surface-to-surface contact, and the tire pattern and size are related to the average friction coefficient.
If we assume that the µ coefficient is constant for the moment we comment, within the parameters mentioned above, the main parameter that increases F_s is N . In other words, it is the share of vehicle weight per tire.
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Basic rule 1:
Keeping “µ” constant, if N increases, F_s increases, if N decreases, F_s decreases.
Now let’s examine why and how “N” increases or decreases. Our assessment is for spring suspension systems, but applies to all suspension systems within their parameters.
The task of the suspension is not only to provide driving comfort and / or safety. It is the system that transfers the load of the vehicle on the chassis to the axles and then to the wheels. That is, one task of the suspension system is to provide useful articulation .
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What is useful articulation ?
It is the state of articulation in which the weight of the vehicle on the chassis can be transferred to the axle as much as possible when the vehicle is articulated.
Let’s give a brief information about springs. There is a special coefficient (k) for each spring that determines the behavior of springs under load, that is, the character of the spring. This coefficient is the ratio of the force applied to the spring (F_y) to the amount of elongation or shortening (X) caused by the spring. (within the scope of Hook’s law)
That is, the force on the spring is equal to the product of the spring coefficient and the spring deformation.
F_y = k * X .
The force F_y on the vehicle spring is also the normal (perpendicular to the surface) force transmitted by the vehicle’s tire to the ground. In other words, the more load the springs in a vehicle suspension system can transfer to the tire, the higher the “N” within the framework of the basic rule 1 we mentioned above. The more “N” gets, the more F_s gets. The more F_s increases, the higher the upper limit of traction, the higher the upper limit of traction, the more successfully and in a large amount the vehicle can transfer the power from the engine to the road and move forward.
Now let’s examine the change in the force transmitted by the tire to the ground under off-road conditions. It will be more understandable to make this examination with numerical examples.
Suppose we have a vehicle with a total weight of 2200 kg. Let’s assume that the same amount of load goes to all four tires of this vehicle.
Let’s assume that the weight of the front and arc axles of this vehicle is 100 kg each.
That is, let’s assume that 2200/4 = 550 kg of load on each tire of the vehicle, 100/2=50 kg remaining on the axle (2200-2*100)/4=500 kg comes from the vehicle’s superstructure.
Let’s assume that the spring in the vehicle suspension system is 60 cm long when unloaded and shortens to 40 cm when the vehicle is loaded on it.
F_y = 500 kg
X=60-40=20cm
K = F_y / X = 500/20 = 25 kg/cm.
We can say that all movements that disrupt the distribution of the load transferred from the tires of the vehicle to the ground are falling diagonally.
We will evaluate the vehicle falling on the diagonal for 4 basic situations. All reviews are for the vehicle we have considered above. It has been assumed that there is no difference in the ground conditions of the individual tires and that all tires can transmit power within the same limit. If a situation contrary to this acceptance occurs, the new situation will display a different behavior within the framework of the same theories.
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1- Standing on flat ground:
In this case, equal load will go to all tires.
N = 500+50 = 550 kg
F_s = µ * 500 kg.
As long as the traction can stay below F_s, the vehicle will be able to drive. If the power from the engine tries to transfer more force from the tires to the ground than F_s, all tires are expected to spin.
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2- Articulation in the amount of partial weight from the vehicle superstructure and the amount of weight that can be transferred from the entire axle:
In this case, let’s assume that the arcs falling diagonally and extending are 50 cm, and the shortening arcs are 30 cm.
F_y_1 = K * (60-50) = 25 * 10 = 250 kg
F_y_2 = K * (60-30) = 25 * 30 = 750 kg.
In other words, only 250 kg of the vehicle weight will be transferred to the tire from the elongated springs, and 750 kg from the shortened springs.
N_1 = 250 + 100/2 = 300 kg
N_2 = 750 + 100/2 = 800 kg.
F_s_1 = µ * 300 kg
F_s _2 = µ * 800 kg.
It should be noted here that while the vehicle can transfer the same weight to all tires, the friction force, that is, the upper limit of traction, which is 500*µ kg, is 300*µ kg for two diagonal tires with extended springs. This means that these two tires will slip sooner. If you fall diagonally on a sloping ground, extra traction will be required in order to move the vehicle against gravity, thus reducing the upper limit of traction in this way may prevent the vehicle from moving. On the other hand, in the other two diagonal tires, the spring of which was shortened, the upper limit of traction was 800*µ kg. This means higher road holding capability for those tires. However, if the tires falling to the traction limit of 300*µ kg slip and slip, the vehicle cannot continue on its way if there is at least 1 differential lock.
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3- Articulation situation where no weight can be transferred from the vehicle superstructure and the weight can be transferred from the entire axle:
In this case, let’s assume that the arcs falling diagonally and extending are 60 cm, and the shortening arcs are 20 cm.
F_y_1 = K * (60-60) = 25 * 0 = 0 kg
F_y_2 = K *(60-20) = 25 * 40 = 1000 kg.
In other words, only 0 kg of the vehicle weight will be transferred to the tire from the elongated springs, and 1000 kg from the shortened springs.
N_1 = 0 + 100/2 = 50 kg
N_2 = 1000 + 100/2 = 1050 kg.
F_s_1 = µ * 50 kg
F_s _2 = µ * 1050 kg.
It should be noted here that while the vehicle can transfer the same weight to all tires, the friction force, that is, the upper limit of traction, which is 500*µ kg, is 50*µ kg for two diagonal tires with extended springs. This means that these two tires will slip very, very soon. If you fall diagonally on a sloping ground, extra traction will be required to move the vehicle against gravity, so reducing the upper limit of traction in this way will prevent the vehicle from going. On the other hand, the upper limit of traction was 1050*µ kg in the other two diagonal tires with shortened springs. This means higher road holding capability for those tires. However, if the tires falling to the traction limit of 50*µ kg slip and slip, the vehicle cannot continue on its way if there is at least 1 differential lock.
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4- Case of articulation in the amount of which no weight can be transferred from the vehicle superstructure and axle:
Under these conditions, the axle self-weight will not contribute to the “N” weight calculated in case 3.
N_1 = 0 + 0 = 0 kg
N_2 = 1000 + 2*100/2 = 1100 kg.
F_s_1 = µ * 0 kg
F_s _2 = µ * 1100 kg.
It should be noted here that while the vehicle can transfer the same weight to all tires, the friction force of 500*µ kg, that is, the upper limit of traction, was 0 kg for two diagonal tires with extended springs. This means that these two tires are spinning empty. On the other hand, the upper limit of traction was 1100*µ kg in the other two diagonal tires with shortened springs. This means higher road holding capability for those tires. However, due to the empty wheels, the vehicle cannot continue if there is no at least 1 differential lock.
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Conclusion and Suggestions:
– Vehicles with high articulation ability fall on the diagonal more difficult, while vehicles with low articulation ability fall on the diagonal much more easily.
The video is a good example of a very advanced crossover and articulation.
– All vehicles that are not exposed to articulation can drive the same way on straight roads, while vehicles with very short springs immediately on uneven surfaces It will fall into position 4. Vehicles with long springs, on the other hand, gradually take 2, then a very short moment. 3rd state and most recent They will fall into position 4.
– The situation is the same with scissor vehicles. The offroad earrings used to increase the articulation ability are placed on the 3rd floor of the vehicle. case it will take longer. As can be seen from the numerical example above, 3. The situation is not very positive in terms of traction. So we can define an equipment for the offroad tag that provides little useful articulation .
– Some vehicles also have anti-roll bar release systems. These are systems that provide benefits, provided that there is still a load on the springs, but 3 or 4. If the situation is reached, they will not show the expected positive effect.
– Suspension systems with very long soft spring coilovers that can be opened and closed in meters, make the vehicle much later. 3. and They are very efficient systems in the field as they reduce it to the 4th state.
– This article is the answer to why we should choose the longer shock absorber + spring option called the lift kit, rather than the chock, which is called the coupe lift, when making upgrade modifications to increase the terrain capabilities of the vehicles.
– We accepted that the vehicle that we examined the subject was a vehicle with a middle lock. Vehicle 2. or in case of slipping or Starting from the 4th states requires either at least 1 differential lock or an EDL-based traction support system . If neither of these systems is present, it will not be possible for the vehicle to continue on its way.
– Let me now connect the subject to another point that I always suggest.
When buying or modifying a vehicle, do not choose a vehicle without a center lock, at least the rear lock is also the front lock if possible, or the locks can be supplied easily and relatively inexpensively as additional accessories. Differential lock is one of the most important elements in off-road conditions.
Vehicle with differential lock + MT tire combination
The differential is generally more successful than the unlocked vehicle + XT tire combination.
Best Regards,
12/03/2020
Süleyman ATILGAN
Contact: Facebook & Instagram


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