Jeff, Do you have any RPM measurements for the OS91 on that APC 14x10? Just want to know how it compares against my old Super Tigre 90 before it bit the dust. I was using a pipe so that's probably worth 3-400 revs. On a good day it would turn a 14x10 at 9,400-9,500RPM on 10% fuel. Trouble was, not all days were good!!

Mike, I would try to get hold of an OS Hanno pump and check if it fits (no better pump ever made IMHO). Failing that, try a Cline regulator. The pipe from the Cline to the carb needs to be short (3/4") to work well but with the OS being a rear mounted needle, that shouldn't be difficult. Allow enough room behind the engine for the regulator & plumbing and don't hard mount the reg. as it doesn't like vibration.

Alan.