MEDFLIGHT Veteran Location: South Webster, Ohio
| I bought a new Evo 90 and YS 91 last August and have been fighting a bad, side to side, high freq vibe ever since. The blades have been balanced several times (main and tails), replaced the main shaft, dial indicated the cluth shaft and hub (x2), balanced fan, tightened belt, tried another set of blades, played with the needles, and installed a boom support bridge. The bridge is the only thing that reduced the vibe but it just hides it a little. The vibe is so bad that the bridge will slide forward about an inch and a half. I'm starting to see the black residue, that vibrations cause, in several places.
Getting a new engine or buying parts and guessing isn't an option. My pockets have bottoms and, quite frankly, I'm tired of screwin' with it. After all of this, I think the problem is the engine (which has about 4 gallon through it). At an idle, it "hums" so bad it is hard to get a screwdriver in slot to adjust the low speed needle. The screwdriver dances all over the place. I really hate to take it out (again) and send it back to YS, just to be told there is nothing wrong with it.
Sorry about this post, but I am totally frustrated. I can see this heli setting on the shelf for a long while. |