Quote:
Originally Posted by jc462
......... Really poking around at options now that I'm in the off-season from racing.......
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Quote:
Originally Posted by choneofakind
In all seriousness though, check out various race tire weights and put that into your decision.
If you're going to be buying tires anyway, might as well get a set that can drop some weight from the outside of the wheel (the spot where mass with have the most effect on rotational inertia).
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Weight saved in tires provides a double gain for both acceleration and braking.
Besides the force (along the chain) necessary to lineally accelerate the mass of both tires (rotating or not, just the mass or weight), an additional torque (radius of sprocket times force also along the chain) is needed to overcome the moment of inertia (angular mass or rotational inertia) of both tires while they change speed.
Force along the chain is limited by the torque of the engine, which has a max.
For that reason, heavier tires will consume more of that torque, slowing the processes of acceleration and braking down.
Discs brakes are superior to drum brakes in that aspect.
Please see:
http://hpwizard.com/rotational-inertia.html
https://en.wikipedia.org/wiki/Moment_of_inertia
As @
choneofakind has explained, for two more or less similar wheel-tire combinations, the mass farther from the center of rotation is the more important to reduce resistance to acceleration and deceleration as much as possible.
In that sense, 16" wheels and tires are better than 17" ones.
