Anybody break a rear sprocket???

We broke a rear sprocket today, not really sure why. Probably cause I've never checked it's tightness for the 75 hours I've got on it....but...Anybody want to speculate???

 

was it the stock one....was your chain to loose or to tight?

 

Stock sprocket, chain adjusted perfect.

 

Yeah the kid, was folllowing me up over three foot jump in trail, and when he landed and hit the gas, he says, he knew there was a problem, and parked it. Sprocket broke into five peices, towed it back to camp with the chain spinning around the axle.....

 

ouch....[img]i/expressions/face-icon-small-sad.gif[/img]

 

Did it have a skidplate? Any rocks in the trail? Big scrapes on the chain?

 

Yeah full PRM skids, , I'm sure nothing hit it.

 

Unless your sprocket was just weak, I'd double check the tightness of the chain. The chain gets tighter as the rear end compresses, the fact that it happened landing a jump makes me think that the chain may have been too tight. Either that or the rear axle wasn't adjusted square and the sprocket was absorbing a sideways load.

 

Good point^

 

In retrospect, the chain tension could have been on the tight side of "perfect". We've ridden it a couple of times since last chain adjustment though. But this was a bit harder ride than those two previous rides.