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Anyone know where I can find a formula to estimate how much power/torque I'll save by switching to wheels and tires that are about 8 lbs lighter each? To keep it simple let's assume I'm taking the weight off evenly (though i'm probably taking of more to the outside of the wheel). So a formula that would tell me how much power/torque it takes to spin up and accelerate about a 22.5" diameter 32 lb disk with uniform mass distribution up to about 60 MPH in about 6 seconds would be nice. I'm sure there are other ways of looking at it too. Ultimately, I'm trying to figure out how the change in wheel weight equates to horsepower/torque savings and what sort of performance gain I can expect. I've pulled out old physics books and looked on the net but I still haven't come up with a good answer. Just guessing - I'd say about 5 - 7 HP.
 
Do a search on rotational inertia... I'm sure there's a lot more than just a single equation to figure this.
 
The problem is that I think the lowering of weight will allow the wheels to get up to speed sooner (theoretical) but will have problems substaining the speed. Flywheel effect.
 
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