Car cornering: side force between external and internal tire

AI Thread Summary
During steady state cornering, the external tire typically experiences higher side forces due to increased normal load from weight transfer. However, in asymmetrical vehicles, the inside tire can have a higher load if it is significantly heavier, potentially leading to greater cornering forces. Factors such as slip angle and toe settings also influence the side load experienced by each tire, with toe-in reducing slip angle on the inner tire and toe-out increasing it. The discussion highlights the complexity of tire load dynamics, emphasizing that vertical load, slip angle, and vehicle design all play crucial roles. Understanding these interactions is essential for optimizing cornering performance in different vehicle configurations.
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Hi all,

During steady state cornering which tire of the same axle experiences the higher side force? I believe the external one for higher normal load due to the weight lateral transfer. Is it true?
 
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The wheel effectively traveling the furthest distance with being exerted to the most pressure, so yes, the outter (external) tyre.
 
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thanks a lot
 
22ashc said:
The wheel effectively traveling the furthest distance with being exerted to the most pressure, so yes, the outter (external) tyre.

I don't think that necessarily follows. The one experiencing the higher force should be the one with the higher load. Yes, on a symmetrical car, this will be the outer one due to weight transfer in the corner, but you could conceivably make a car with one side much heavier than the other, such that even when the heavy side was on the inside of a corner, it would still have a higher tire load than the outside. Then I would expect the higher cornering load on the inside tire.
 
cjl said:
I don't think that necessarily follows. The one experiencing the higher force should be the one with the higher load. Yes, on a symmetrical car, this will be the outer one due to weight transfer in the corner ...
That would translate into a higher vertical load, but the original question is about side loads. One of the factors affecting side loads is "slip" angle, how much "inwards" is the orientation of the tire versus it's actual path. If there's "toe in", then the inner tire has less slip angle, if there's "toe out" (an effect of ackerman steering on street cars for tire wear, not for cornering performance), then the inner tire would have more slip angle (when not cornering near the limits of traction). I'm not sure about the combined effects of vertical load versus side load versus slip angle.
 
In a left hand steady state turn you are dealing with lateral load transfer. This assumes the weight coming from the rear of the car and the cross weight has already shifted and been countered by the spring/ shock ( damper) and is not oscillating. Now in a left hand steady state turn the right front tire and right rear tire will have more load than the other two. Typically the right front is the most loaded but this depends upon where the engine is located..frt wheel drive Ft. engine. RWD Ft. engine RWD rear engine or ft. wheel drive rear engine.
You are correct in that vertical load on a tire increases the tires ability to accept more load ..to a point..for more detail see race car suspension class posts on this forum
 
rcgldr said:
If there's "toe in", then the inner tire has less slip angle, if there's "toe out" (an effect of ackerman steering on street cars for tire wear, not for cornering performance), then the inner tire would have more slip angle (when not cornering near the limits of traction).
1.Why would more slip angle during turns(toe-out) imply less tire wear?The rubber flexes more than it would in toe-in right?Wouldn't this imply more tire wear in toe-out? (in relation to the inner wheel).
 

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