Howdy Fitz. A bunch of folks have used CVTs. I have had one on a Harbor Freight engine for months but have yet to get it on a bike. Shafts on most engines that will work for our thing are 5/8 and needs to be shimmed up. Also a CVT needs to be further reduced, ratio wise for a conventional sprocket drive. I have yet to really work on either of those puzzles but many have with success.