[huckleberry hound]

The Tension cam is correctly installed. All you have to do is look at the drum band close when ON (counterclockwise/up)

Okay the only thing that I can think of then is they mist have gotten grease on the inside of the roller clutch mechanism. Service documents clearly state to avoid getting grease on the inside of the roller clutch. If you do it will cause it to malfunction.

 

[Leyenda]

MacGyver

I checked the cam position and it is correct, but still, the lever will not stay in the ON position. So I've held it in place with a strategically placed ziploc and some superglue - and so far it's working wonderfully. Feels nice not have my derailleur bouncing around on descents again. I ordered another derailleur, but still, nice to know this one will at least serve as a useable backup...

Just FYI, this does work!

 

[fellsbiker]

Thats very similar to what I did. Except theres so much slop in my derailer anyway that its still feels like poop. Its got close to 2000 hard miles on it, its time to replace it.

 

[EJ_92606]

I had a similar issue after regreasing and it turns out I inserted the cam unit in backwards (not the cam orientation, but the whole unit itself)....it will fit but won't work correctly. Look at the manual picture closely and you'll see no hole on the cam unit frame facing out, the side with the hole is supposed to go in first. Take a look at your picture, the side with the hole is facing out.

 

[fellsbiker]

I can't tell by your description, what you are talking about. My photo looks just like the manual to my eyes. Can you maybe draw on the photo and/or manual image to show me what you mean?

 

[EJ_92606]

I can't tell by your description, what you are talking about. My photo looks just like the manual to my eyes. Can you maybe draw on the photo and/or manual image to show me what you mean?

Sorry, I should have posted a pic. It is difficult to describe. Here is a screenshot and the "cam unit" line is pointing directly to the area that I am talking about. If you remove the cam unit you will see one side looks like that diagram and the other side has a hole in it. Hope this helps.

 

[fellsbiker]

But mine in the photo appears to be oriented the same way as the diagram?

 

[EJ_92606]

But mine in the photo appears to be oriented the same way as the diagram?

Here is the hole in yours. Remove and check the other side.

 

[fellsbiker]

That's not a hole, that's just a little scuff mark on the metal.

 

[EJ_92606]

Here is mine in correct orientation after I discovered my mistake.

 

[EJ_92606]

That's not a hole, that's just a little scuff mark on the metal.

ok, but it looks just like the reverse side of mine looked. Perhaps that's not it, but next time it's apart take a look.

 

[acer66]

My GF’s xtr started to do the same thing.
:-(

 

[acer66]

Delete.

 

[jcb208]

Hi new here I found out what this problem is.The metal shaft on the switch lever comes loose and turns slightly stopping the cam moving to a locked position. The replacement part you need is Y5Y198010

 

[B. Rock]

So I've been struggling with this a bit too. Took the cover off to see what was going on. It looks like as the derailleur cycles, the spring is being pushed outward as shown in the 2 pics below. The first pic is with everything centered where it should be, the 2nd is after ~10 cycles and the on/off lever starting to move. The only thing keeping the spring on the clutch is the cover - with the cover off it will pop off/separate if keep cycling it. I'm wondering if the spring-clutch interface is just worn down and now asymmetrical? It also looks like the whole derailleur flexes a bit allowing things to get distorted and off center, although all of the bolts I checked are tight.

 

[B. Rock]

Update. Got a new clutch for $16. Didn't change anything. Will be trying the level that @jcb208 suggested next. Something is allowing the clutch to move outward as the derailleur cycles, which seems to be allowing the lever to undo itself.

Edit: for what it's worth, the shimano dealer's manual lists replacing the lever alongside replacing the clutch. Could be telling that when one wears out, so does the other.

 

[acer66]

Gf’s xtr has a little grub screw at bottom of the body which supposedly adjust the clutch tension.
Tried that and she said it made a difference.

 

[B. Rock]

Yep. Tried that from just engaging all the way to maxing it out. Still works itself undone.

 

[Cleared2land]

^^^^ Does everything work correctly with the cover on?

 

[B. Rock]

Nope.