Chain conversion and ratio?
 

I'm actually building a bobber. I have a new tranny and a 3" open primary. What parts r needed behind the primary plate with a chain drive? Sprocket...but a spacer first? Sprocket and then something before the primary plate? Can I get a list of what I need and the order it goes in. And what is a good front and rear sprocket size for a 111" engine with a six speed tranny?

Pull the primary off, remove the pulley nut, reverse thread turn it to the right to loosen it. Remove the pulley replace with the chain sprocket, reverse procedure.Are you trying to keep the same ratio as your belt? Ratios work like this, count the teeth on your trans pulley say 32, then count the teeth on the rear pulley say 66. Divide the 66 by the 32 =2.062. Now do the same for the chain sprockets you will be putting on. Say 23 tooth trans and 48 tooth rear sprockets. 48/23=2.086. Pretty close.

No no...there's nothing there as of now. Just a engine and transmission. I wasn't sure what parts were needed on the trans shaft when using a chain and sprocket final drive. Just a spacer, sprocket, and nut? Then bolt on the primary?