Found source of low end vibration

[monker]

Went out riding on Saturday and found the source of a bad low end vibration that I was having. Last weekend I could feel it around 15-25mph, especially when letting off the throttle. After riding a while it would put my hand to sleep.

Anyway, turns out the bolt that holds the bottom gears on the drive shaft backed out. It came right through the chain case and took a big chunk out of there. I'm not sure on damage to the gears or chain yet, but will find out tonight. :x

 

[SumpBuster]

Monker, was that bolt ever removed? I think that one gets loctite blue. I double checked my top sprocket nut a few weeks ago, as I had all that stuff out when changing the track. Everything was tight. The tapered sleeve on the jackshaft inside the bearing slid out, but now I think it was never put back in tight, when the engine was removed last year. The blue sled has 2200 miles now, and everything looks perfect on my monthly checkup..but nothing on that has ever been apart, except for the two rear suspension bolts.

 

[DYNAREX]

Monker-
i wish my vibration was that easy-i get it with just the engine running and no clutch on it-i think i need a new gear reduction shaft-bearing or damper is bad on it