R.A.V.E. VALVES

[toostrokin]

WHAT DOES R.A.V.E. STAND FOR AND WHAT DOES A RAVE VALVE DO?

[Technical Support]

Rotax Adjustable Variable Exhaust valve. It's a sliding valve that moves up and down in the exhaust port. It raises and lowers the top of the exhaust port the piston sees. In the down position at low RPMs, it raises compression for better low end power. At higher RPMs it raises, giving lower compression and more area for higher top RPMs.

[biggunz]

Does a 717 engine have one of these valves?

[1fastski.com]

no only the 787 and 951

[stevepaulus]

well were on the subject.....what the heck causes raves to blow the springs off continuosley, and twist the bellow blowing oil all over? 2nd motor

[1fastski.com]

happins once its a defect , happins twice its a shame it wasnt done right [img]graemlins/buck.gif[/img] . check all your Orings you could have one or more missing . they should not pop off unless dirty .

[stevepaulus]

new motor with about an hour on it.....in the process of rebuilding the carbs. Anyways, the upper spring on the mag bellow was off and the bellow was twisted. No missing parts, and i can't imagine it being that dirty after little use.

[Bill O'Neal2]

If that clyinder is running way too rich on fuel, it will fill the rave valve diaphram with raw fuel and push the diaphram off of the rave piston.

[stevepaulus]

thanks bill, that explains it........since i'm a dope and mixed way too much break in oil, not to mention did it the wrong way.