Redline 53H engine vibration

[KevinDudley]

Just completed a build on a Titan X50.
First Engine Start: Engine started with ONE burst of starter, ran fine at idle.

I noticed immediately an excessive vibration coming from the engine.
Even at idle the vibration "buzzes" your fingers if you touch the mixture needle or put your fingers on the engine itself.

The vibration translates clear through the tail boom and ALL parts are buzzing.

This is all at idle.

This cannot be correct.

This is a NEW X50, never flown, just completed kit, FIRST start on engine.

Any ideas??????

Thanks....

[KevinDudley]

My follow up......
I removed the engine and "balanced" the clutch disk by removing material on the top of the disk.

It was slightly out of balance.
I also "freed" up the bearings on the starter shaft. They were a near press fit and were very hard to get out. Biffed shaft with sandpaper so bearings would slide freely onto shaft.


I took them out and the starter shaft so I could shorten the starter shaft by 0.020" to be sure the engine crank shaft end was not pressing up against the starter shaft.

This seemed to free the starter shaft up slightly so that it would spin more freely.
Maybe mattered, maybe not.

Any, vibrations did reduce considerably.
I also think that when the engine is broken in and running "cleanly" in 2 cycle mode the vibes will be less.

Thanks....