XT problems when upshifting with clutch on
11-13-23, 02:40 AM
#1
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XT problems when upshifting with clutch on
Hi! I have a 12sp XT derailleur with the adjustable clutch. The clutch has been giving me some issues since day zero. I'm currently using an M6100 cassette, but have had the same issues with an M7100.
The thing is the shifting is smooth as butter, except that with the clutch turned on the chain tends to stick to the 51T and refuses (or it's really slow) to upshift to the 2nd sprocket. If I adjust the clutch to have less tension, then it shifts perfectly, but at that moment, it barely does its job with the chain hitting the chainstay at any meaningful bump. I have serviced the clucth at regular intervals, so that's not the problem. The cable has also been changed and it's perectly smooth. B screw tension is also correct.
In any case, the clutch, even when engaged, seems kind of weak compared to the Apex 1 one on my gravel bike, where the chain never hits the stay. I don't care that much about that since I have a neoprene protector on the MTB stay, but I don't understand why it's so hard to upshift with it on. On the other hand, I feel like this XT is one of the smoothest transmissions I have used, except for this 51T thing.
Has anyone had a similar experience? Am I doing something wrong?
The thing is the shifting is smooth as butter, except that with the clutch turned on the chain tends to stick to the 51T and refuses (or it's really slow) to upshift to the 2nd sprocket. If I adjust the clutch to have less tension, then it shifts perfectly, but at that moment, it barely does its job with the chain hitting the chainstay at any meaningful bump. I have serviced the clucth at regular intervals, so that's not the problem. The cable has also been changed and it's perectly smooth. B screw tension is also correct.
In any case, the clutch, even when engaged, seems kind of weak compared to the Apex 1 one on my gravel bike, where the chain never hits the stay. I don't care that much about that since I have a neoprene protector on the MTB stay, but I don't understand why it's so hard to upshift with it on. On the other hand, I feel like this XT is one of the smoothest transmissions I have used, except for this 51T thing.
Has anyone had a similar experience? Am I doing something wrong?
11-13-23, 03:18 PM
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Hi! I have a 12sp XT derailleur with the adjustable clutch. The clutch has been giving me some issues since day zero. I'm currently using an M6100 cassette, but have had the same issues with an M7100.
The thing is the shifting is smooth as butter, except that with the clutch turned on the chain tends to stick to the 51T and refuses (or it's really slow) to upshift to the 2nd sprocket. If I adjust the clutch to have less tension, then it shifts perfectly, but at that moment, it barely does its job with the chain hitting the chainstay at any meaningful bump. I have serviced the clucth at regular intervals, so that's not the problem. The cable has also been changed and it's perectly smooth. B screw tension is also correct.
In any case, the clutch, even when engaged, seems kind of weak compared to the Apex 1 one on my gravel bike, where the chain never hits the stay. I don't care that much about that since I have a neoprene protector on the MTB stay, but I don't understand why it's so hard to upshift with it on. On the other hand, I feel like this XT is one of the smoothest transmissions I have used, except for this 51T thing.
Has anyone had a similar experience? Am I doing something wrong?
The thing is the shifting is smooth as butter, except that with the clutch turned on the chain tends to stick to the 51T and refuses (or it's really slow) to upshift to the 2nd sprocket. If I adjust the clutch to have less tension, then it shifts perfectly, but at that moment, it barely does its job with the chain hitting the chainstay at any meaningful bump. I have serviced the clucth at regular intervals, so that's not the problem. The cable has also been changed and it's perectly smooth. B screw tension is also correct.
In any case, the clutch, even when engaged, seems kind of weak compared to the Apex 1 one on my gravel bike, where the chain never hits the stay. I don't care that much about that since I have a neoprene protector on the MTB stay, but I don't understand why it's so hard to upshift with it on. On the other hand, I feel like this XT is one of the smoothest transmissions I have used, except for this 51T thing.
Has anyone had a similar experience? Am I doing something wrong?
if the roller is too close to the cassette, it won't allow the chain to derail easily.....there's not enough room to bend the chain into a "derail" state....
the chain acts like it's "stuck on the big sprocket"...
"clutch off" allows the cage to move with every bump.. that will create windows of time that the roller moves away from the sprocket enough to derail the chain....
experiment with the b-screw, and/or lower the derailleur somehow...
A "too short" chain can also cause hesitant downshifts from 1st....
can you post a side shot pic of the der. and cassette in the "stuck in 1st" condition?
also, a side shot of the drivetrain in the 12th gear too?
Last edited by maddog34; 11-13-23 at 03:31 PM.
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11-13-23, 07:29 PM
#3
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B-screw adjustment for these super wide range cassettes is different from normal ranges. In its closest position, the jockey pulley must clear the current cog plus the next larger one, so when the downshift occurs, the pulley doesn't bash into the side of the cog. That means adjusting the b-screw for more clearance, which can make for more sluggish upshifts (shifts to smaller cogs). So see if you can adjust for a smaller gap without making downshifts more difficult or impossible.
