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Discussion Starter #1
I have a project where I need to chain drive a 21" wheel. Low horsepower type thing. I don't really wanna lace up a 21" rim to a rear hub because its a low buck type thing. So I am proposing drilling a sprocket to fit the studs that the spoke flange on about a 1980 model wheel attaches with. These are four M6 studs. I do not have a wheel on hand yet, but does anyone see a glaring issue with this?
 

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Four M6 studs doesn't sound substantial enough, to me. What does the spoke flange do in the original config? What stresses would it see? Without a cush drive, especially, I would think that those small studs would just rip out ..even with as low as 10 HP. If this is for a motorcycle, look at the original application. Usually it would have 6 M8 studs, or better. With a larger wheel diameter, you will have a greater moment arm reacting against the drive sprocket studs.
 

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Discussion Starter #4
I will have to get the wheel in hand and take a look. Alot depends if i can add studs or reinforce it in some way. I may end up lacing a wheel after all.



The flange originally carried radial load from the spokes and I would estimate 50% of the torque load from braking (as half the spokes attach to it). Braking load is different from the "pounding" load of an engine however as its primarily a single direction torque when the brake is applied. With engine braking and power pulses I could see where the M6 studs could be quickly fatigued if they are not ripped from the hub. Thanks for the input.

I would go w/ the disc but I want the drum :/
 

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Discussion Starter #6
Well. What this is for is a semi sort of pannier tank AJS replica. I'm thinking lacing to a more suitable hub will be best.
 
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