Shimano XT 12 speed strange shift symptoms

PB Forum :: Mechanics' Lounge
Shimano XT 12 speed strange shift symptoms
Previous Page | Next Page
Author Message
Posted: May 8, 2022 at 19:19 Quote
I'm dealing with some strange symptoms on my XT 12 speed drivetrain. When shifting up into an easier (larger cog) gear it's like I need to shift it and then push the shifter a tiny bit farther for the chain to actually shift into that cog. If i just do a single shift it will not catch and shift up. I have to give it a little tiny nudge. If I adjust the barrel adjuster out to add some cable tension this issue goes away but then the derailleur wont shift down into a harder (smaller cog) gear. It's like I can have one or the other but not both.

Things I have checked so far

1. Replaced cable and housing, no change
2. Cleaned and lubed drivetrain
3. Replaced chain
4. Checked hanger is straight with hanger alignment tool
5. Checked b, high. and low limits. They are all good.
6. Checked hanger and derailleur bolt for correct torque.
7. Greased derailleur clutch

The drivetrain (not inclusing the chain which I just replaced) has 900 miles on it and only one season of riding.

Posted: May 8, 2022 at 19:44 Quote
Try adjusting high [small cog] limit screw in a bit-1/4-turn

Posted: May 8, 2022 at 20:26 Quote
https://www.youtube.com/watch?v=E-iAxH32NlI
Watch this video, it shows how to take apart & grease the cage pivot bolt on the derailleur.
Mine was quite rusted after 1 yr. Take note when he removes the bolt from the cage, only unscrew with the 4mm hex & hold (or put the T25 in a vice). The piece with the T25 is pressed into the cage. I did turn it on mine & was worried that it might not go back in properly, but it pulled itself back in when I tightened it back together,
Just thought I should warn you ahead of time.
Long story short, it made things like new again.

Posted: May 9, 2022 at 9:49 Quote
Thanks for the recommendations but neither of those worked. I was hopeful that cleaning the main pivot would work because it was dirty and rusty in there but nope Frown

Posted: May 9, 2022 at 11:37 Quote
Check your chain is the right way round. Shimano HG to the outside.

Posted: May 9, 2022 at 14:51 Quote
It must have been the rear derailleur because replacing it fixed it. I took it apart and cleaned it but noticed some play in the pivots which had me skeptical. Even after cleaning it was not working. Something in the derailleur had to be causing some friction.

Posted: May 12, 2022 at 9:52 Quote
After about a year of riding I had a mech that developed a similar issue , I watched every video on setting up XT 12sp, indexed the thing a hundred times, read and reread the Shimano manual, greased clutch and pivots, replaced chain. Finally called Shimano and they warranted it and the issues went instantly.

Posted: May 13, 2022 at 5:51 Quote
No issues with my 12 speed XT setup, although using a Deore Cassette. Rock solid so far after 1.5 years

Posted: May 25, 2022 at 20:19 Quote
if you shift into the biggest cog, on the other side of the cage ( looking from non drive side) there will be a little 51T line for the B tension. line any of the teeth on the 51 tooth cog up with the line.

Posted: Jun 4, 2022 at 9:27 Quote
Be sure to set your B tension with you on the bike.
The gap grows as suspension sags. Too big of gap=your symptoms.

Previous Page | Next Page

 
Copyright © 2000 - 2022. Pinkbike.com. All rights reserved.
dv65 0.006536
Mobile Version of Website