I had a high frequency vibration on my 912UL. I throttled back to 5000 rpm and it went away. going to full power brings it back. I checked the carb balance and did a full mechanical and pneumatic. Kitten smooth at idle and on the ground at WOT.

reaching 5300 and higher I get the vibe back. I had a new propeller still in the box and for giggles, I installed it. Better performance and the vibration is back. The engine has 400 hours on it, so I"m not thinking it needs new rubber yet, but ... maybe.

anyone else see anything like this in the rotax 912ul?
Its a Kitfox IV and I have about 1000 hours on it.
thanks.
Wheels