Will,

That's an interesting comparison. I'm assuming that Rich was running an 11x9 on his AR (seems small) otherwise he wouldn't have assumed that the pipe length setup would work equally well on the short stroke Classic - true?

Otherwise, if he propped down, rpm'ed up, would he not naturally expect to need a shorter exhaust setup?

I've been looking at the stock exhaust setup for the NR Speed/13 and it is mighty short (especially for a "long stroke", albeit high timed, engine). But Rossi's often did have very short exhausts on 11x7 props.

David