SchmidtMotorWorks wrote: ↑Thu Mar 09, 2023 11:02 am
I'm curious, who believes that DVs claim that reducing mass increases rear wheel power?
Hint; The work being done was reduced, the power was not increased.
This can be computed more precisely than dyno or track testing can.
If dyno or track testing contradicts the computation, the testing is flawed.
Rear Wheel Power Increases - The Spin Zone
Here are eight ways to get big rear-wheel POWER INCREASES without having your ENGINE make one hp more.
David Vizard photographer Johnny Hunkins photographer
Dec 12, 2006
https://www.motortrend.com/how-to/0602p ... -increase/
There is power consumed by angularly accelerating a body, the power is given by = I x alpha x omega
where
I = mass moment of inertia (kgm^2)
alpha = angular acceleration (rad/s^2)
omega = rotational velocity (rad/s)
take a 10kg flysheel 12" in diameter accelerating from 2000-7000 in 7 seconds
the power consumed at 7000rpm is
I = 1/2mr^2 = 0.5*10*0.1524^2 = 0.116
omega = 7000 * 2 * pi / 60 = 733 rad/s
alpha = (733 - 2000 * 2 * p / 60) / 7 = 75 rad/s^2
power = 0.116 * 733 * 75 = 6377 watts = 6.3 kW