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Can someone help my brain out?
Probably not.
In your problem, you can essentially disregard the rim size for most purposes, since the difference between the tyre radius (the lever trying to turn the wheel) and the brake track radius (the lever trying to stop it) is only a small fraction of either dimension.
The problem with small wheels is rarely the slight difference in heat capacity, it's the moving of the tipping pivot to a lower position, which lowers the limiting deceleration before you endo.
gbj_tester
Murphy's_Law
Can someone help my brain out? I'm trying to wrap my head around some pretty simple and logical physics....
Say you have a normal size wheel, 28" for example with a rimbrake.
now you have the same setup, same rimbrake, but on a smaller wheel, say 20"
is the braking power of the brake stronger on the big wheel or the small wheel?
Now, since the point where the brake grips relative to the rotational mass of the wheel is the same on both wheel sizes (brake grips at the rim) the braking power should be the same. But then the rotational mass of the smaller wheel is smaller, so does the brake work better on the smaller wheel?
Now this hasn't really got a realistic background, i've just seen these 20" road bikes with rim brakes and got thinking.