Shifting on it's own
10-13-14, 02:05 PM
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Shifting on it's own
I have a Trek CrossRip with Claris components. The front in a triple, and when I'm in the middle ring, and one of the middle gears in the back, the bike jumps cogs between two gears, usually when under load. Sometimes it even feels like the chain gets held up; kind of like when you pedal and then the chain has to "catch up".
I took it to the LBS for an adjustment, and they said everything was fine and gave me a lesson on trimming.
Does it sound like it might be a chain issue, or just an adjustment? It only happens while in that middle chainring, and when in a certain gear on the rear cassette.
I took it to the LBS for an adjustment, and they said everything was fine and gave me a lesson on trimming.
Does it sound like it might be a chain issue, or just an adjustment? It only happens while in that middle chainring, and when in a certain gear on the rear cassette.
10-13-14, 02:19 PM
#2
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Does it sound like it might be a chain issue, or just an adjustment?
Its just a guess ..
The RD and shift lever clicks may be out of synch .. sight matters more than sound & they saw what I Cannot.
10-13-14, 09:34 PM
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Put the bike in that gear.
Then look at the derailleur from behind the bike. Is the upper pulley directly under and in line with the cog? If not, probably need to adjust. Is the derailleur cage perfectly vertical, assuming the bike is? If not, derailleur hanger may be bent.
Then look at the derailleur from behind the bike. Is the upper pulley directly under and in line with the cog? If not, probably need to adjust. Is the derailleur cage perfectly vertical, assuming the bike is? If not, derailleur hanger may be bent.
10-13-14, 09:39 PM
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How old is the drivetrain? Some of the symptoms described sound like they may be chainsuck related.
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“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
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10-13-14, 10:32 PM
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10-13-14, 11:10 PM
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Either way, take a moment and oil the chain and see if that helps. Other than skipping from a stiff link or chainsuck, I don't know of anything that acts as you describe.
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An ounce of diagnosis is worth a pound of cure.
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
10-14-14, 04:57 AM
#7
Mechanic/Tourist
Did the problem gradually develop over time or start rather suddenly? If the latter was there maintenance or an incident that directly preceded the problem? Have you carefully inspected the problem cog in the back to look for any burrs or any debris between cogs?
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