Here I go again. We still have a bunch of old 600cc sprints setting around with no place to race. They race pretty good with TQ's and it would sure be nice if someone would make a place in their rules to let these old 600's with chain drive run with TQ's. I got two That would like to run ever once in a while. Yeh ! I know "there is a difference". I bet you might even get an Ambrose to race a few times. They out grew TQ's.