Derailleur cage hitting cog - help appreciated
08-18-21, 09:57 PM
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Derailleur cage hitting cog - help appreciated
Hey everyone -
So I'm finally wrapping up the Trek Mountain Track I've been working on (found it in a dumpster, repainted it, put some new parts on it, etc.) and I'm so close to being done but I'm having some shifting issues. I replaced the 12-28 7 speed cassette with a 12-32 7 speed cassette to get a little more of a crawler gear. I put a new chain on but I'm getting some pretty severe rubbing where the cage of the RD hits the teeth on the 2nd largest cog (but it is completely smooth on the largest cog). Is this an issue with my chain length? I thought I sized it correctly, but then I couldn't get into the largest cog so I added back a link and now I'm having this current issue.
RD is a Shimano Acera X. The bike was shifting perfectly before I replaced the cassette / chain, so I don't think the derailleur hanger is out of whack. The problem gets worse as I shift from my biggest chainring to the smallest one (3x). I have the b-tension screw all the way in with no change. High and low limits are set correctly (I think). What could this be? I've attached a video of the issue below:
So I'm finally wrapping up the Trek Mountain Track I've been working on (found it in a dumpster, repainted it, put some new parts on it, etc.) and I'm so close to being done but I'm having some shifting issues. I replaced the 12-28 7 speed cassette with a 12-32 7 speed cassette to get a little more of a crawler gear. I put a new chain on but I'm getting some pretty severe rubbing where the cage of the RD hits the teeth on the 2nd largest cog (but it is completely smooth on the largest cog). Is this an issue with my chain length? I thought I sized it correctly, but then I couldn't get into the largest cog so I added back a link and now I'm having this current issue.
RD is a Shimano Acera X. The bike was shifting perfectly before I replaced the cassette / chain, so I don't think the derailleur hanger is out of whack. The problem gets worse as I shift from my biggest chainring to the smallest one (3x). I have the b-tension screw all the way in with no change. High and low limits are set correctly (I think). What could this be? I've attached a video of the issue below:
08-19-21, 05:17 AM
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08-19-21, 01:04 PM
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It may be that the larger cog is not compatible with that particular derailleur. You could try shortening the chain a bit . On my vintage bikes with horizontal dropouts I just back out the stop screws in the dropout and it clears the cog better , but you are kind of stuck with the way that dropout is.
08-24-21, 11:12 AM
#4
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Hey everyone -
So I'm finally wrapping up the Trek Mountain Track I've been working on (found it in a dumpster, repainted it, put some new parts on it, etc.) and I'm so close to being done but I'm having some shifting issues. I replaced the 12-28 7 speed cassette with a 12-32 7 speed cassette to get a little more of a crawler gear. I put a new chain on but I'm getting some pretty severe rubbing where the cage of the RD hits the teeth on the 2nd largest cog (but it is completely smooth on the largest cog). Is this an issue with my chain length? I thought I sized it correctly, but then I couldn't get into the largest cog so I added back a link and now I'm having this current issue.
RD is a Shimano Acera X. The bike was shifting perfectly before I replaced the cassette / chain, so I don't think the derailleur hanger is out of whack. The problem gets worse as I shift from my biggest chainring to the smallest one (3x). I have the b-tension screw all the way in with no change. High and low limits are set correctly (I think). What could this be? I've attached a video of the issue below:
Video
So I'm finally wrapping up the Trek Mountain Track I've been working on (found it in a dumpster, repainted it, put some new parts on it, etc.) and I'm so close to being done but I'm having some shifting issues. I replaced the 12-28 7 speed cassette with a 12-32 7 speed cassette to get a little more of a crawler gear. I put a new chain on but I'm getting some pretty severe rubbing where the cage of the RD hits the teeth on the 2nd largest cog (but it is completely smooth on the largest cog). Is this an issue with my chain length? I thought I sized it correctly, but then I couldn't get into the largest cog so I added back a link and now I'm having this current issue.
RD is a Shimano Acera X. The bike was shifting perfectly before I replaced the cassette / chain, so I don't think the derailleur hanger is out of whack. The problem gets worse as I shift from my biggest chainring to the smallest one (3x). I have the b-tension screw all the way in with no change. High and low limits are set correctly (I think). What could this be? I've attached a video of the issue below:
Video
Chain Catches Against Adjacent Cassette Cog - Bike Forums
