trans problems xj750

i got bike up and running and took it for a test ride and kept poping out of gear 1st and 2nd no probs with rest so i pulled motor and pulled potom pan off and found bit and chunks of plastic


http://i1370.photobucket.com/albums/ag2 ... 0f6ce2.jpg

 

Your primary chain guide is disintegrating.

The bike has a "Hi-Vo" chain that runs a jackshaft with the alternator on one and and the starter clutch on the other. Since it's not a "true" primary chain (it doesn't transfer primary drive from engine to gearbox) Yamaha only fit it with a solid plastic chain guide.

They are known to break apart in chunks. Those chunks often end up wedged in the shifter forks. If you pull the LH "shifter" cover (gasket required) there is a hole in the inner case through which you can view the transmission and shifter forks. Quit often the hunks can be plucked out.

The real fix is to split the cases and replace the chain guide.

 

i figured it was a chain guide. just wanted to make sure. i realy dont want to split case but i have to to make sure i clean out all debrie because sump filter is cloged with tiny chunck of plastic as well

 

Unfortunately I dont have much to add by way of tips, but I will say this.

This guy. I like this guy. Welcome to the forums.

 

Anybody know where to buy new chain guides cant find them anywhere only used ones. May end up making my own

 

Did you try sending a PM to chacal? I find his parts listings completely impossible to navigate and worthless (Sorry, buddy!). If you message him with what you are looking for, he will give you the listing with part numbers which makes it 100X easier to order what you need.

Len/chacal is your friend when it comes to getting parts for these bikes. Even if the part is no longer available from Yamaha, He probably has it available and in 3 different color options.

If you cant find one of his posts to click on the private message link, go to the forum index and go to his parts listings.

 

Hit "ctrl f" while your in his parts listing will make your life a little easier.

 

so my buddy that does a lot of mx racing asked me what would happen if i just cleaned out the bits and slapted the engine back together since it just runs the alternator and starter clutch. theres no load and he said hes done worse with some of his 4 stroke bikes and never had any major issues.

now me on the other hand could not give him an answer because it there for a reason i supose, and second he also rebuilds his engine every 2 years or so and i dont nor want to. so out of curosity what would happen i am more familar with car engines

 

Chain slap is chain slap. You can ride on it until it is more convenient to replace, but eventually it will begin to damage things.

I have a Yamaha XS bike, and they are known for primary chain problems. I can ride it, and I can hear the chain slapping. Sooner or later, it will saw through the engine. The best part about XJ bikes is that it can be fixed. Not so much with the XS line.

Enjoy the fact that you can fix the problem, and do it.

 

everywhere i look it says its a complete gasket kit. i am not seeing the gasket for the case itself. is there something else im suposed to use because it almost looks like the case was glued together

 

It was....with Yamabond. Loctite 515 is also a good choice (and it doesn't begin to cure until the parts are mated, so you can be called away and still put the casees together).