Shifting not as sharp after a rock strike

tonyride

tonyride

Don't piss off the red guy
I have a new bike with Shimano Deore 12-speed rear derailleur, chain, and cassette. The bike arrived perfect and the shifting was spot on. It remained this way for a couple of rides until on a steep rocky climb when the rear wheel brushed up against a rock on the drive side and it wedged the cage and lower jockey wheel into the spokes. Luckily I heard the racket early and stopped pedaling immediately so I didn't crank down on it much to avoid any further damage. I carried the bike up to the top to assess the situation. I was able to free the cage and jockey wheel from the spokes with the bike upside down. Then I checked the alignment of the derailleur and the hanger. The hanger looks pretty straight (BTW, it uses the SRAM UDH) but the derailleur cage looks a little bent but was bending outwards away from the wheel instead of inwards as you'd expect. I checked the shifting and it wasn't as precise as before but was still shifting. I tightened up the L limit screw a bit to keep it from overshooting the largest cog and did the remainder of the ride even if I'm unable to shift into the lowest gear. When I got it home I checked the hanger alignment with my Park Tool hanger alignment tool to check it out. It was off a bit so I straightened it out. I put the derailleur back on and still wasn't shifting like it did when new. I took a closer look at the derailleur itself and specifically the cage. I did some research and found out that all of the Shimano 12-speed derailleurs from Deore to XTR have that little bend outward and a slight twist to the cage. So over the weekend I took long close look at the cassette, chain, derailleur, and I also put a new hanger on it. I adjusted the limit screws, checked the B-tension gap, etc. I got it to where it shifts perfectly from the highest gear (smallest cog) all the way up to the lowest gear (largest cog). But on the way back it's a different story. From 1st to 2nd and 11-12th gear it'll shift with just one click. But everything in between it won't shift with just a single click but it sounds like it is trying. I click again and it'll jump 2 gears. It is as if its not springing back hard enough. Any thoughts? Sorry for the long message.
 
tonyride

tonyride

Don't piss off the red guy
I would bring it in to a shop and let the professionals fix it but I suspect they're busy getting people's bikes ready for biking season and I don't want my bike sitting at the shop for weeks when it is still mostly rideable.
 
Santapez

Santapez

Well-Known Member
Team MTBNJ Halter's
Your rear derailleur is probably FUBARed if it went into the spokes.

The problem with modern derailleurs having complex cages means it's hard to bend them back "straight".
 
tonyride

tonyride

Don't piss off the red guy
Santapez said:
Your rear derailleur is probably FUBARed if it went into the spokes.

The problem with modern derailleurs having complex cages means it's hard to bend them back "straight".
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I was afraid someone would say that. I have a feeling that the derailleur is messed up but I wanted to hear some opinions. I know with 12 speeds the tolerances on these complex mechanical components must be pretty tight so any slight deviation would mess up the shifting. Next question, should I stick with Deore or should I move up to SLX or even XT? Worth the extra cost?
 
JimN

JimN

Captain Wildcat
Team MTBNJ Halter's
@UtahJoe put his derailleur into his spokes twice recently. I hit my derailleur too often to rock the 12-speed drive train and its super tight tolerances. I hit my 10sp derailleur on a rock and then just bend it back a little at a time until I stop hearing clicking sounds and it's good as new.
 
A Potted Plant

A Potted Plant

Honorary Sod
JimN said:
@UtahJoe put his derailleur into his spokes twice recently. I hit my derailleur too often to rock the 12-speed drive train and its super tight tolerances. I hit my 10sp derailleur on a rock and then just bend it back a little at a time until I stop hearing clicking sounds and it's good as new.
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I have the same 11speed derailleur that has been snapped off the hanger and the shifter cable locked up the rear wheel.

@tonyride get a hanger alignment tool or make one and see if correcting the hanger will correct the shifting. That typically does it for me, but I've over estimated the skill set on this forum 2 times to many. If you think that is to much to take on leave it to the shop.

If you weren't so far I'd lend you my alignment tool.
 
Karate Monkey

Karate Monkey

Well-Known Member
tonyride said:
I was afraid someone would say that. I have a feeling that the derailleur is messed up but I wanted to hear some opinions. I know with 12 speeds the tolerances on these complex mechanical components must be pretty tight so any slight deviation would mess up the shifting. Next question, should I stick with Deore or should I move up to SLX or even XT? Worth the extra cost?
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Probably more a question of how long it takes to get. Lead times are super long.

FWIW, after one too many altercations with branches, my XTR was not working properly anymore. It would work, but not well. Trying to bend it back into shape using a pry inserted through the parallelogram resulted in either snapping the bar or bending it, depending on how hard it was.

They're pretty stout, is what I'm saying.
 
bergsnj

bergsnj

Well-Known Member
try loosening the cable with the barrel adjuster on the shifter 2 or 3 clicks clockwise. sounds like the cable is too tight
 
onetracker

onetracker

Well-Known Member
jimvreeland said:
AXS would've hit the rock, gone into crash mode, and you would've never even noticed anything was wrong.
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Serious questions. So I do not understand this? If the AXS derailleur hits a rock then goes into crash mode, how does the derailleur or hanger not get bent? Especially when the derailleur is at the extreme positions. Also in the case of sucking up a stick (which is my biggest nemesis especially in the shoulder seasons) how does stuff not get bent?
 
Karate Monkey

Karate Monkey

Well-Known Member
onetracker said:
Serious questions. So I do not understand this? If the AXS derailleur hits a rock then goes into crash mode, how does the derailleur or hanger not get bent? Especially when the derailleur is at the extreme positions. Also in the case of sucking up a stick (which is my biggest nemesis especially in the shoulder seasons) how does stuff not get bent?
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Still can, but the derailleur is built to rotate back without damage. I mean, most of them are, now, but you can still damage cables, for instance.

Also, in a stunning display of something actually working as they intended it, the Universal Derailleur Hanger actually does a good job protecting a derailleur in a crash/hit.

OFC, if you're a chowder head and hear racking/clunking coming from the rear wheel, and decide to just power through it, nothing is gonna help you.
 
Steve Vai

Steve Vai

Endurance Guy: Tolerates most of us.
onetracker said:
Serious questions. So I do not understand this? If the AXS derailleur hits a rock then goes into crash mode, how does the derailleur or hanger not get bent? Especially when the derailleur is at the extreme positions. Also in the case of sucking up a stick (which is my biggest nemesis especially in the shoulder seasons) how does stuff not get bent?
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The derailleur goes limp to stop that energy from being transferred to the frame or hanger. The derailleur itself is so overbuilt it'll catch a stick and just skid the rear wheel. I do this pretty much every time I ride with gears because I forget how long the cage actually is. But like Ninja 🐒 said, if you ignore it and pedal, there's no saving you.
 
onetracker

onetracker

Well-Known Member
Karate Monkey said:
Still can, but the derailleur is built to rotate back without damage. I mean, most of them are, now, but you can still damage cables, for instance.

Also, in a stunning display of something actually working as they intended it, the Universal Derailleur Hanger actually does a good job protecting a derailleur in a crash/hit.

OFC, if you're a chowder head and hear racking/clunking coming from the rear wheel, and decide to just power through it, nothing is gonna help you.
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Thx. I have zero experience with AXS.

Good most of the time so I get this with mech derailleurs. But some times it happens so fast, a stick can do real damage in a blink of an eye especially if traveling downhill. With older say 9 speed mech derailleurs, often a new hanger and some rough alignment and things were eaisly fixed. Newer Shimano 11 spd derailleurs are a bit more temperamental.
 
Steve Vai

Steve Vai

Endurance Guy: Tolerates most of us.
The first gen Shimano clutch derailleurs are god awful. You need a new cable and clutch rebuild every 2 rides.
 
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