Originally Posted by Dan
Den, I'm curious about your engine drive set up. Are the parts off the shelf or did you machine a sleve and add bearings? I really wan't to try some thing like that. A couple yrs back went to an aerospace shop and they wanted buku bucks. (now am in school for precision machining, lol. Got tired of trying to get shops to make stuff for me.)
good that i dismantled the pulley/sprocket last night.
i drill 3$ pulley in axle diam size, then make bigger opening for both end using lathe for bearing housing (you can see the outer bearing and just the same for the inner). and the chain sprocket, weld into mounting that fit with inner side of the pulley (also as stopper for inner bearing). the stopper for outer bearing is the 4 bolts that also act as holder for entire assembly.
once the pulley assembly put into the axle, you can have the idea that between pedals/axle and pulley/sprocket are independence due to the internal bearing.
here is some pic and let me know for more detail required