U-Joint? problems

[chris61]

My '82 XJ1100 has a problem in first gear under moderate to heavy acceleration. There is, what seems to be, a slip in the u-joint, resulting in what can be best described as a slip in the drive. The engine surges and there is a "hop", almost like the clutch is being engaged and released really quick. This only happens in first gear, and only under moderate to heavy acceleration. I hope my description of the problem didn't sound too stupid; it's a bit tough to describe. Thanks for any advice.
Chris

[TheDjost]

A U-joint can't slip. Unless this is some new U-joint that I have never seen before. Though I have never had a look at the one on our bikes, I'm pretty sure that that isn't your problem.
You said that it felt like the clutch slipping, ant you may be right. These are wet clutches, and if the oil is too thick(too cold, wrong weight), too slippery(synthetic not made especially for wet clutch), then the clutch might slip.

If your oil is getting old, change it to some quality dino juice. That mignt help.

Or you could be right and I.m stupid and there is really something wrong in your drive train. But I wouldn't suspect a U-joint first.

-Justin

[chris61]

Thanks Justin......but if it was a clutch problem, wouldn't it affect all gears and not just first? Thanks.........Chris

[Ken Talbot]

This might be a problem with splines or it could be in the transmission. Use the search tab at the top of the page to look for 'splines' and see if anything in those articles sonds familiar. Then try 'first gear slip' in the search tool to see if something there sounds more like it.

[Mike Hart]

Chris, I bet you have the "2d gear" problem - except in XJ's, it's usually first gear that does that. The problem first shows up only under full throttle w/ load, then gradually becomes worse til you get it (as you report) under moderate acceleration.

Check out the Repairs/Transmission forum. TC is working up a new pictorial tip for that too, stand by...

Good luck, and welcome to the forums.

[skids]

You might want to remove the rear wheel and clean out the hard crap that builds in the radial gear under that plastic cover. The first time I took care of that I just couldn't believe how hard that stuff was (I was the second or third owner of the XS11E). Relube it. It would also be a good time to lube the spline gears in the drive shaft joint, in case the grease zerk is not doing a good job. The other things that could be happening are dogs slipping in and out of the slots in the transmission, or a slipping HiVo chain (not fixable as far as I know).

[TonimusMaximus]

If it was really your u-joint, it would go "c-clunk" all the time at pretty much any speed. Certain gears in the tranny do go bad all on their own. Makes no sense if you think of the tranny as a unit, but think of it as seperate gears instead. Same as cars. Usually the first gear to go is reverse. Check out the picturized tranny tutorial in the Tech section. It'll help a lot.

[TopCatGr58]

Dreaded 2nd/1st gear malady!

Hey there Chris,

From what you've described, you have the dreaded 1st gear worn/hop syndrome that the earlier bikes describe as the 2nd gear syndrome. The contact surfaces between the dogs and slots of the meshing gears have worn down, and so they slide apart and slip in and out of gear under the stress of acceleration.

I've repaired 2 XJ's that exhibited this in their 1st gears first, but their 2nd gears weren't far from failing as well. My 81 also had it occur to the 1st gear first, but 2nd also failed shortly thereafter.

It can be repaired without pulling the engine or tearing the case halves apart, but it does require a bit of work. Sorry I haven't made the time to finalize the Tranny tech tip for this repair. If you haven't found the Yahoo group, you can go there and sign up and then read and see the pictures on how to do it there.

Also, in the tech tips, Ken Talbot's pages have several on this as well, just look for the 2nd gear problem!

T.C.

[chevy45412001]

ive had the same problem with my xj. turned out to be a loose nut inside the inspection cover ,on right side. the set nut on the adjustment bolt.readjusted the setting according to manuel tightened set nut no more problem.at least with that part. but i still have a slipping clutch prob that wont go away.ive tried every thing in theese fourmsbut no luck. am now running with extra steel plate,heavy duty springs,one year old clutches.still at speed (5th gear ) when i hit the throttle it slips ,depending on how hard i hit it the slip gets worse.sorry now im rambling. hope that was a start to your question.

[stevec5000]

chevy45412001, I have a set of Barnet steel plates that will fix any slipping problem that you can have for postage. They don't have the dimples like normal plates have so are a lot harder to release. I tried them but can't use them because they won't release enought to allow normal shifting.
I have the same problem with first as the others described above so I always have to pull out in 2nd while slipping the clutch. It's hard to believe a slipping clutch can't be easily repaired because mine never slips but I have a problem getting it to release. If the steel plates are flat, and most of them are not, and the friction plates are good and springs not weak it can't slip unless it's turbo charged and you're using synthetic oil.

[chris61]

Thanks to all who replied. I'm glad (in a selfish sort of way) that it's not just my bike that does this. T.C. ... I went to the Yahoo site and downloaded the fix that you detailed so well. I'll give it to the guy who does my work and turn him loose if he wants to take a whack at it. After this is taken care of (and the new float needle put in carb #2 to fix the drip), it'll be good as new, or as close to new as possible for a 21 year old bike. Again, thanks to all!

[dwales]

Chris,
My 81 Special did the same thing, before my son wrecked it. I am familiar with all the advice given here, and what I felt was not anything described here. I never did find the problem though. Hopefully you get it figured out before I get mine put back together.

[wildbill]

This sounds like your splines in the rearend might not be engaged good.Worth a check.Pull rear wheel off and check,clean real good,put new grease on splines and on those on rear wheel.Line everything up good,make sure the splines engage.Also make sure the axle nut is tight.This might cure your problem.Good luck,Hope this helps