Human Powered Vehicles Built for Speed

[BP-Revo]

Well, with our 5" diameter tires (or 2" with touring cars) we achieve more contact patch by increasing width.

With bicycle tires which are at least 20" in diameter, they can still be very thin but can have quite a large contact patch due to the diameter.

But that is quite impressive, I must say.

[shizzon]

Originally Posted by BP-Revo

Well, with our 5" diameter tires (or 2" with touring cars) we achieve more contact patch by increasing width.

With bicycle tires which are at least 20" in diameter, they can still be very thin but can have quite a large contact patch due to the diameter.

But that is quite impressive, I must say.

contact patch for a road bike tire at 100-120 psi is about the size of a postage stamp if not smaller, but i wouldn't think that breaking traction would be a problem for these things the way they are geared.

with all the power our cars have and the relatively short distance to get to top speed traction is more important, and finding a balance between rolling resistance and traction will be key.

if there was near unlimited runway then super skinny tires and wheels would greatly increase the speed, as you could slowly apply throttle to prevent loosing traction.

[BP-Revo]

Originally Posted by shizzon

contact patch for a road bike tire at 100-120 psi is about the size of a postage stamp if not smaller, but i wouldn't think that breaking traction would be a problem for these things the way they are geared.

with all the power our cars have and the relatively short distance to get to top speed traction is more important, and finding a balance between rolling resistance and traction will be key.

if there was near unlimited runway then super skinny tires and wheels would greatly increase the speed, as you could slowly apply throttle to prevent loosing traction.

I'm not saying that he has a massive contact patch, only pointing out that even though the tire might be super skinny it may provide much more contact patch than someone might think due to the diameter.

I do agree that if we put touring car width (or even skinnier) tires on all our vehicles that it would greatly increase top speed, but the new WFRCC rules have tire requirements for MT's, so that class is still screwed (tires have a diameter and width requirement).

I wouldn't mind going to that exact same stretch of road as they did and maybe having a chase car follow the RC to keep it in range. 5 miles is plenty of space for any solid 500hp to get up to speed, be it a Viper, Porsche Turbo Carrera, Corvette Z06, M5/M6, etc.