Re: free wheeling
Welcome to the forum. You asked about the S.A hub holding up to the motor. Are you using a shift kit? If not the bike's rear hub is uneffected by the engine. The power is applied to the spokes and rim and there really is no appreciable stress put on the hub other than the bearings due to the speed. If you are running a Sick Bike Parts shift kit then you should listen to their advice concerning upgrades to hubs. Hope this answers your question.
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