Tonight I went to put my new P3X on the trainer and when I pulled out the rear thru axle, my rear derailleur came off. Wasn't expecting that. The cable also pulled out of the unit. I reassembled everything and put the plug back in, but there's a lot of slack in the chain now (clearly the derailleur is not picking up the slack). The shift buttons work but the chain is barely above the stay. So, the questions are (i) what did I do and (ii) how do I fix it?
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Re: Ultegra Di2 Rear Derailleur Problem [Patrick E]
[ In reply to ]
First you need to refit the hanger tab properly.
Then you need to realise that the derailleur must intrerface with the hanger correctly.
What you have done is not rotated the derailleur far enough backwards when you fitted it and the tab has not engaged properly.
Unfortunately, by doing this you may have damaged the tab or bent the hanger by doing the bolt up while they were interfering with each other.
Refit hanger/ through axle fitting properly, checking for damage. Use low strength locktight to prevent it happening again.
Align hanger.
Refit derailleur properly, checking for damage before doing so. Make sure you rotate it far back and watch as you do it up that the tab engages cleanly.
Then you need to realise that the derailleur must intrerface with the hanger correctly.
What you have done is not rotated the derailleur far enough backwards when you fitted it and the tab has not engaged properly.
Unfortunately, by doing this you may have damaged the tab or bent the hanger by doing the bolt up while they were interfering with each other.
Refit hanger/ through axle fitting properly, checking for damage. Use low strength locktight to prevent it happening again.
Align hanger.
Refit derailleur properly, checking for damage before doing so. Make sure you rotate it far back and watch as you do it up that the tab engages cleanly.
lyrrad wrote:
First you need to refit the hanger tab properly. Then you need to realise that the derailleur must intrerface with the hanger correctly.
What you have done is not rotated the derailleur far enough backwards when you fitted it and the tab has not engaged properly.
Unfortunately, by doing this you may have damaged the tab or bent the hanger by doing the bolt up while they were interfering with each other.
Refit hanger/ through axle fitting properly, checking for damage. Use low strength locktight to prevent it happening again.
Align hanger.
Refit derailleur properly, checking for damage before doing so. Make sure you rotate it far back and watch as you do it up that the tab engages cleanly.
Thanks. Figured out what I did last night and fixed it. Don’t think I did any damage and everything appears to be working like normal. However, something is clearly not right with the way the derailleur is attaching (or not attaching) to the frame since it gets very loose as soon as I pull out the thru axle.