You are hereForums / By Discipline / Mountain (off road) / MTB Gear / Chain twist & Dérailleur pulley not springing back
Chain twist & Dérailleur pulley not springing back
T'was cleaning the drive train with the rear wheel off and for the life of me, could not understand how the chain twisted like this.
Short of unlinking it and twisting it out, is there another quick way to untangle this mongrel?
Other google posts of jiggling it like a lipton tea bag didnt work...
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Ok had to chain break it and get a quick link. It was probably the fastest way to fix it so thats done.
Now, the lower pulley on the derailleur isnt springing back (2nd pic) and hanging loosely.
Does that mean a new one is on the cards or am I missing something and an easy turn of a screw is all it takes?
Boy, i hope it means i dont have to get a new derailleur...
- Login to post comments
- Bookmark & share
I'd try dropping the chain off the crankset and over the pedal, so it only loops around the chain stay.
Then you can untangle it and put it back over the cranks.
If it was OK before, you can get it back that way without breaking the chain.
Good luck.
I should add that the loop around the chain stay should also go through the front D.
Is there another twist anywhere else in the chain? If you can bring the two together they'll cancel each other out.
Otherwise, instead of working with the small loop pictured bring the upper parts of the chain together (if possible?) to create a bigger loop and try to roll the loop out with less resistance(?). May not be helpful to you but the last time anything like this happened to me was a good 20 years ago.
I'd say good luck but it's more a question of logic. More specifically, unless part of the chain is actually bent it can't not be possible to fix without breaking the chain. Said differently: The chain is intact and 'fixed' together, if it can twist into this shape it can be twisted back, the trick is in how it is manipulated. Perhaps create the opposite effect somewhere along the chain then bring the two together?
Is it possible your chain dropped on the outside of the pedal and you then spun them around hooking the chain and giving it a twist? Maybe try that in reverse. Drop the wheel out, maybe bring the rear mech forward to give yourself more slack.
My thinking (maybe some experience as well, but I can't be certain it has actually happened) says it's the only way that could happen without breaking the chain.
Is it possible that the cage flipped through 360 degrees nd that caused your twist? That would mean that the cage is now in need of rotation through 360 degrees anti clockwise to re-tension the spring....
I haven't time to check, but I'm sure an X9/X0 has a stop on the cage pivot that should prevent this.......
Hope you get it sorted.
It looks like your tension spring is either broken or has been twisted out from the retainer holes in the derailleur body.Take the derailleur off,undo the C clip that holds the spring inside the derailleur body and check its integrity.Putting it back together is a bit tricky as you have to pretension the spring as one end is in its retainer hole and press the cover back into the derailleur body and press the clip back on.Good luck,,Freddie.
looks like a twisted rear der to me as well.
Happened to me in the mudfest that was the 1st Capital Punishment, when I had some mega chain sucky thing happen. Flipped the bike upside down to see what the problem was and thought I had somehow trashed the rear XT der as it all looked weirdly out of position. A few minutes of fiddling and I was able to flip it back and all was about as good as it could be that day.....
Have never been game to try to re-create in a workshop environment.
@Slowpup - Yep it is an X9 and gawd knows how you managed to identify it on the pic posted. Thats some serious wiki knowledge you have there on components. Not sure how the pulley did a full 360 but will give it a try when i get home.
But I do recall a catch on it, so it may have went in the other direction.
@Fastfreddie - If it is the spring thats busted. I dont imagine they sell springs spare huh?
From memory you don't have to worry about the spring really once you've got it back in, just be wary when pulling the wheel out as the rear derailer can spin and put a loop in your chain like it's done. Ideally get it fixed down the line but from memory it doesn't change the performance in any noticeable way.
I've had it happen years ago on some bikes. Simply take the wheel of rotate the rear derailer a full revolution so you can feel the spring tension and sort that loop out and then stick the wheel back in and off you go.
Just fluked it!
Thanks fellas... you lot should be named the brain trust!
Right on the nail. Just needed a full revolution. The catch on the X9 isnt very effective so that did the job. Cheers!
Love,
Flubs