At what track width does traction become the limiting factor of corning speed?
ElectricStreamliner said
Jun 5, 2022
I was wondering about this and what better place to ask regarding bicycle tires and trikes going around corners without lifting a wheel.
Archer321 said
Jun 5, 2022
In my opinion, there are several other factors involved to determine how fast a vehicle can corneras limited by traction.
Number of wheels and layout. (3 wheels or 4? 2 in front or 2 in rear?)
Overall weight of vehicle
Weight balance of vehicle (front to rear)
Effective height of center of gravity
Wheelbase length (probably matters more with 3 wheels than 4)
Tire contact patch size and stickiness of rubber compound
The racetrack's minimum radius of turn
Also I wouldn't say that traction is ever the limiting factor for cornering speed as determined by wheel track width. The factors listed above do not change with vehicle track width. What does change is the vehicle's tendency to flip over.
In order to maximize cornering speed a vehicle needs:
Maximum wheel track width you're willing to have,
Lightest weight possible,
Proper weight balance (for a reverse trike this usually means a front weight bias)
Lowest possible center of gravity.
These are just my thoughts. I reserve the right to be wrong
ProEV said
Jun 6, 2022
< At what track width does traction become the limiting factor of corning speed?>
This depends on the grip generated by the tire contact patch, height of the center of gravity, distance between the center of gravity and the tire contact patch and car momentum, so there is no single answer.
If you want to make your vehicle less likely to flip, the normal options are lessen tire grip by running higher tire pressure or harder tires, increase track width, move weight lower in the car.
A less obvious solution on a three wheeled delta vehicle is shift weight onto the rear wheel. This makes the vehicle more inclined to spin than flip.
ElectricStreamliner said
Jun 17, 2022
Thank you for your replies.
I learned that in solving one problem I have come across many more problems to solve haha.
Spinning which would cause understeer in a delta (front wheel slip) and avoid flipping maybe good for a delta while it is very bad for a tadpole because it causes oversteer increasing the likelihood of flipping.
Driving one of the rear wheels of the delta allows the front wheel to have less traction resulting in beneficial loss of traction without compromising traction of the drive wheel or roll stability.
A lot to think about.
-- Edited by ElectricStreamliner on Friday 17th of June 2022 02:04:06 AM
ProEV said
Jun 17, 2022
ProEV wrote:
A less obvious solution on a three wheeled delta vehicle is shift weight onto the rear wheel. This makes the vehicle more inclined to spin than flip.
Sorry, I made a mistake. I wrote delta when I meant tadpole.
On a tadpole 3 wheel vehicle (two wheels in front, one in rear), flipping is caused by the front outside tire (outside in relation to the turn) having enough grip that rather than the outside tire sliding, it sticks and the inside front tire comes off the ground.
If instead, the rear tire loses grip first, the vehicle will pivot around the front outside tire, spinning rather than flipping.
A spinning car is generally preferable to a flipping car. Of course, whether spinning or sliding, if the vehicle reaches something to trip it up like a curb, it might flip anyway
I was wondering about this and what better place to ask regarding bicycle tires and trikes going around corners without lifting a wheel.
In my opinion, there are several other factors involved to determine how fast a vehicle can corner as limited by traction.
Number of wheels and layout. (3 wheels or 4? 2 in front or 2 in rear?)
Overall weight of vehicle
Weight balance of vehicle (front to rear)
Effective height of center of gravity
Wheelbase length (probably matters more with 3 wheels than 4)
Tire contact patch size and stickiness of rubber compound
The racetrack's minimum radius of turn
Also I wouldn't say that traction is ever the limiting factor for cornering speed as determined by wheel track width. The factors listed above do not change with vehicle track width. What does change is the vehicle's tendency to flip over.
In order to maximize cornering speed a vehicle needs:
Maximum wheel track width you're willing to have,
Lightest weight possible,
Proper weight balance (for a reverse trike this usually means a front weight bias)
Lowest possible center of gravity.
These are just my thoughts. I reserve the right to be wrong
< At what track width does traction become the limiting factor of corning speed?>
This depends on the grip generated by the tire contact patch, height of the center of gravity, distance between the center of gravity and the tire contact patch and car momentum, so there is no single answer.
If you want to make your vehicle less likely to flip, the normal options are lessen tire grip by running higher tire pressure or harder tires, increase track width, move weight lower in the car.
A less obvious solution on a three wheeled delta vehicle is shift weight onto the rear wheel. This makes the vehicle more inclined to spin than flip.
Thank you for your replies.
I learned that in solving one problem I have come across many more problems to solve haha.
Spinning which would cause understeer in a delta (front wheel slip) and avoid flipping maybe good for a delta while it is very bad for a tadpole because it causes oversteer increasing the likelihood of flipping.
Driving one of the rear wheels of the delta allows the front wheel to have less traction resulting in beneficial loss of traction without compromising traction of the drive wheel or roll stability.
A lot to think about.
-- Edited by ElectricStreamliner on Friday 17th of June 2022 02:04:06 AM
Sorry, I made a mistake. I wrote delta when I meant tadpole.
On a tadpole 3 wheel vehicle (two wheels in front, one in rear), flipping is caused by the front outside tire (outside in relation to the turn) having enough grip that rather than the outside tire sliding, it sticks and the inside front tire comes off the ground.
If instead, the rear tire loses grip first, the vehicle will pivot around the front outside tire, spinning rather than flipping.
A spinning car is generally preferable to a flipping car. Of course, whether spinning or sliding, if the vehicle reaches something to trip it up like a curb, it might flip anyway