Chain Guide/ Transmission

Ok, here's the story. My friends 82 750 max stopped shifting gears on friday. I figured it was a piece of primary chain guide in the transmission - and I was right! However, the piece is much lager than I expected, its 1" by .5" by .5" (it has two whole 'teeth' for those who have seen the guide). this chunk seems big to me, is it, or is it average? Now I know this is bad news, but my question is now that the piece is out and he's back on the road, how much time before we have a total failure?? He's hoping to get to the end of the season, then get a doaner engine and swap it in. Anybody have any similar experiences they can share??

 

I've seen guides where the whole thing apart from the ends are in little pieces! Another bit could fall into the transmission and lock it again. If the guide is in that condition what is the chain like?

Does the motor seem to be really rattly on idle?

I rode my bike for several months like that but replaced the bottom end with a donor. When I checked the old chain it was so loose as to be hitting the engine cases. When loose they also hit the oiler making the problem worse. There is also the chance that the chain could fail.

The replacement motor could also have the same problem. Consider replacing the chain and guide on his motor insted; the cases need to be split and the crank needs to come out but the top end (pistons etc.) can stay assembled.

 

It should be mentioned that the situation poses a danger.

Should the remnant fail and a large piece enter the transmission ... the ensuing locking-up of the gears will send the motorbike out-of-control.

Operating the motorcycle in this condition is done with the obvious threat and at your own risk.

If you can hear the problem; there's no greater warning.

 

I'm aware of the lockup danger, and I made him aware, but thanks for pointing that out rick.

Kiwi, the motor runs great, no noise, even the usual XJ rattle isn't there.

thanks guys, keep the comments and info rolling in

 

I had a similar experience two years ago. Split the case and replace the guide, no other options that are good I'm afraid.

 

So the chain should be OK if there is no rattle, good news! The guide is cheap so would be well worth doing his motor, sooner rather than later.

 

$22 USD at most internet shops.

 

thanks for the help guys, I'm trying to talk him in to changing the guide, but he doesn't want to get off the bike long enough to let us get at it :S