You also hogged out your spokes backwards. Should've left the most meat and the slowest transition at the inner radius and not the outer radius. This would've made the fatigue and the rotational weight better. If you used a CNC machine and did everything symetrical, I would think the balance would be close.
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Really Guys ? other than the above comment Which is true, I dont think he did a bad job.
The outer diameter of the flywheel is doing no work after the Bendix disengages. Remeber this is not a charging flywheel, and he lightened the ring gear, the mass that is farthest away from the center has the most effect. also the lighter it is, the less balance means, as such less effect on the bearings
I would have cut 8 windows instead of 4 and put the thicker webs at the bottom, other than that, provided that the alloy and temper of the aluminum is correct, I would run it
that said I would not expect the motor to idle well at all and probably vibrate like a mofo under 4000 rpm
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