I'm on my second build. I'm using what I have at hand because money's tight. I have a schwinn ten speed bike and a used poulan chainsaw. I used timing gears and chain from a Camry as wheel drive. Since the saw turned clockwise and I didn't want to attach it to my bikes wheel sprocket and have pedals turn too fast I used trans from a washer to go to opposite side of bike. Didn't have enough timing chain so I've used v-belt pulleys from saw to trans.