Shimano XTR Please help!!

[thisismyotherbike]

I am clutching at straws here, maybe two things to check.

 

Is the clutch engaged? My mate always forgets to re-engage his. Also, is the chain directional and if so is it in the right direction.

 

I wouldn’t expect either of these two things to result in your issue, but may as well check everything.

XTR chain is directional so you may be onto something?

 

The "Shimano" writing on the chain should be facing right, in other words on the outside facing away from the bike.

[Captain Fastbastard Mayhem]

Okay, that's fine. Next step. From one of the pics, Looks like the cage may be sliiiightly twisted near the bottom, causing the 2 wheels to be non-parallel.

[Eldron]

Chain routing is right...

 

The der wheels look off centre - check if they're the right way around (and if the right wheel is in the right place - I've seen wheels swapped during hasty rebuilds).

[Dicky DQ]

Chain routing is right...

 

The der wheels look off centre - check if they're the right way around (and if the right wheel is in the right place - I've seen wheels swapped during hasty rebuilds).

Nothing had been adjusted except chain has been replaced. This is not an xtr chain.

 

Parts of the cage are now worn due to the rubbing of the chain caught between the wheel and the cage.

 

Can't be twisted as it is a carbon cage.

 

Problem has been there since new, hence the change change.

 

1,421 km total on the bike. 14 rides in total.

[DieselnDust]

It's an XTR problem.

But you can improve the issue by increasing the jockey pulley wheel cage tension.

To do this you need to remove the derailleur, unscrew the jockey cage stop and unwind the spring tension. Remove the cage and while you have it off clean the pivot bushing it swings in. I guarantee you will find a lot of rust.

Now to increase the cage spring tension. There are two holes where the spring can be captive. The derailleur comes shipped with the spring in the rear most hole which provides the least amount of tension. Move the spring tab into the most forward hole and re insert the jockey cage. Wind the cage one revolution and re insert the cage stop pin.

The cage should now pull more tension onto the chain.

[DJR]

Too long a chain length will cause the chain to slap around more and make it more likely for it jumping off, especially when in the smaller chainring and smaller cogs which make the chain slacker. Perhaps the chain was left too long when it was replaced.

[Dicky DQ]

It's an XTR problem.

But you can improve the issue by increasing the jockey pulley wheel cage tension.

To do this you need to remove the derailleur, unscrew the jockey cage stop and unwind the spring tension. Remove the cage and while you have it off clean the pivot bushing it swings in. I guarantee you will find a lot of rust.

Now to increase the cage spring tension. There are two holes where the spring can be captive. The derailleur comes shipped with the spring in the rear most hole which provides the least amount of tension. Move the spring tab into the most forward hole and re insert the jockey cage. Wind the cage one revolution and re insert the cage stop pin.

The cage should now pull more tension onto the chain.

I will check this, just unfortunate that a superposed to end product has this foible 

[Dicky DQ]

Too long a chain length will cause the chain to slap around more and make it more likely for it jumping off, especially when in the smaller chainring and smaller cogs which make the chain slacker. Perhaps the chain was left too long when it was replaced.

The Clutch is engaged, I have tried both options.

I have shortend the chain from original delivery spec by 2 full links already and believe that if it is any shorter it will be too short to engage the 42T

[Dicky DQ]

Chain routing is right...

 

The der wheels look off centre - check if they're the right way around (and if the right wheel is in the right place - I've seen wheels swapped during hasty rebuilds).

E everything is straight an parallel, however the angle of the photo could be misleading as well as the fact that the side of the cage has been worn quite a bit on the inside (about 40% of the material has been chaffed away already can lead you to think it is off center.

[dave303e]

Have you checked the jockey wheels for play side to side on rotation or are they running true?

[DieselnDust]

also check for  a broken tooth on the lower pulley wheel

[dirtypot]

I had this on my XTR.  I replaced the pulley wheels (twice - second time with the larger Sram wheels), got a new inner cage plate, adjusted the derailleur hanger (have the tool) set the cage tension, stripped lubed and tensioned the clutch mech properly, put on a new chain - the works.  I would have the chain fall off the lower pulley wheel whenever the terrain got bumpy.

 

In the end the way I solved the issue was by changing to XX1.  Haven't looked back since.

 

EDIT - I had trouble free XTR'ing for about 10,000km before the issue started.  Nothing happened which I'm aware of to have caused the issue.  Maybe it just got old.  XTR is the racy one not the long term one after all. 

[Pieterlab1]

I had XTR with a 32T Oval Black chain ring on my Giant Anthem Advanced. Did about 5000km's without any problems.

[Grey Hubs]

I long shot here...could the limit screw loosen during your ride?

 

Sorry, read the problem incorrectly...Move along, nothing to see here....

[DogMTB]

I had the exact same issue. I used Pratley to fill the area the chain had worn and it fixed my issue.

 

Here is how it looked:

 

 

I did some extensive research and here is what you must check:

 

- Bent derailleur cage

- Jockey wheel is spinning correct direction (look for small little arrow)

- Limit screws are perfect

- Jockey wheel cleaned of any grime

[Spoke101]

I find this interesting as there should be no chain growth as with dual sus bike.

So I would say the issue is with chain tension or a faulty part that's throwing the chain.

 

I have read all the comments but here's my checklist:

Chinring: running straight and teeth not bent.

Jockey wheels: top and bottom are different as well as directional, plus lateral play.

Chain: Shimano writing facing away from the bike and no bent/broken links.

Derailleur: Cage tension and clutch tension.

 

As for a solution build up the worn carbon with epoxy and then look at making the entrance gap for the chain coming in to the derailleur smaller again by building up the inside of the cage with epoxy.