Join Date: Nov 2008
Location: Bay Area, Calif.
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Originally Posted by iFold
nope, I'm talking about two different bikes with different wheel sizes. Assuming that both have the same mass and you apply the same amount of power to accelerate it, the smaller wheels would go faster.
If both the bikes and the wheels have the same mass (and mass distribution) then the energy required to accelerate them to a given speed will be equal. Keep in mind that the smaller wheel will need to be spinning faster (higher rpm) for a given linear speed of the bike. Work out the math and the wheel size is not a factor.
Of course in practice smaller wheels will tend to be lighter so there might be an advantage - but you specified equal mass wheels. There could also be an aerodynamic advantage to the smaller wheels. OTOH, if the tire construction and pressures are kept fixed then there tends to be a rolling resistance advantage for larger wheels. Both of these are small effects - details of both bikes and other factors (e.g. speed reached) would need to be specified to see which one is greater in a particular case.