Chain rub on compact crank
#1
Thread Starter
Senior Member
Joined: Jun 2013
Posts: 164
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From: NYC
Bikes: Jamis Icon Pro
Chain rub on compact crank
Hey guys, I am getting chain rub on my new road bike
JAMIS BICYCLES
At first, I was getting chain rub with the small chain ring up front and large 1-3 rear. I was able to fix that by setting the the limit screws so it would not rub on the third, and I dont use the first two anyway so they are not a problem. However when I am in the large front and last three small rear I am also getting chain rub. Is this common with a compact crank? Normally I dont use the last two much but sometimes when I get a good tailwind, I do notice the problem. Just afraid that it would cause excessive wear long term, not to mention its annoying. Any help would be appreciated, thanks!
JAMIS BICYCLES
At first, I was getting chain rub with the small chain ring up front and large 1-3 rear. I was able to fix that by setting the the limit screws so it would not rub on the third, and I dont use the first two anyway so they are not a problem. However when I am in the large front and last three small rear I am also getting chain rub. Is this common with a compact crank? Normally I dont use the last two much but sometimes when I get a good tailwind, I do notice the problem. Just afraid that it would cause excessive wear long term, not to mention its annoying. Any help would be appreciated, thanks!
#2
You probably shouldn't cross chain (large front, large back or small front, small back). It's hard on the chain because of the angles involved.
You should be able to use the small/large (either way) without excessive chain rub. I reckon the shop you bought it from can adjust it for you.
You should be able to use the small/large (either way) without excessive chain rub. I reckon the shop you bought it from can adjust it for you.
#3
Senior Member
Joined: Dec 2011
Posts: 230
Likes: 1
Search on how to use "trim" on the front derailleur. Basically if everything is properly adjusted re cable tension and limit screws, partial swings of the lever, one click, should get you to intermediate FD positions that don't rub in those problem gears.
#5
Senior Member
Joined: May 2013
Posts: 4,400
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From: SF Bay Area
Bikes: Bianchi Infinito (Celeste, of course)
What size bike? Generally, smaller bikes have more issues with chain rub than larger frames, due to the chain angles.
Some rub may occur with small---small or large-large combinations. You should never encounter rub in a small-large (or vice versa) combination. Rub in those combinations is an improperly set derailuer.
Some rub may occur with small---small or large-large combinations. You should never encounter rub in a small-large (or vice versa) combination. Rub in those combinations is an improperly set derailuer.
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neilcrumpton
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