"Chehalis Jeff" wrote in message
oups.com...

Remember,
always do compression tests with the throttle wide open.



Just for kicks, take a compression test on a two-stroke motor with the
throttle closed, throttle open, and your hand over the carb blocking off all
air flow. You will find that the compression numbers are all very close. Why
you ask? Because the exhaust port is open to ambient air until the piston
ring closes it off. On a two stroke, the compression only builds when the
exhaust port is closed off by the top ring. Try it, if you don't believe.

Bill Grannis
service manager