Front derailleur rubbing on chain.

[geopat]

This happens only in my 2 top gears.

Any quick tips to sort? Will the cable tensioner alone fix this?

Thanks

 

[The Brewer]

Change ring or don't use those gears

Just try and keep the chain straight

 

[geopat]

Its not like I'm crossing the chain though. The problem is only on large ring at the front and the 2 smallest cogs at the rear i.e. my 2 fastest gears.

 

[The Brewer]

Have you adjusted the limit screws Pat.

I tend to look for youtube videos to try to help me, but I sometimes come unstuck

This seems to offer good advice

 

[Pat "5mph"]

Have you adjusted the limit screws Pat.

I tend to look for youtube videos to try to help me, but I sometimes come unstuck

This seems to offer good advice

Happened to me also: in the front middle ring could not use the back highest gears, 6th and 7th. Actually the video linked by the Brewer is the clearest on you tube imo, but a bit hard to do if you don't have a proper bike stand. I improvised, fiddled a wee bit, now I can use all my back gears in the middle ring, but the front don't shift anymore
I fear I went overboard with the cable tension, need to fiddle some more but you tube does say it is a difficult adjustment to do.
Btw, my lbs guy says that all the gears are supposed to work only in the middle ring, but maybe he said it only to get rid of me

 

[geopat]

Thanks, I did have a quick look on YT but didn't find anything as clear as this one.

The very problem is highlighted in this video. Apparently I just loosen cable tension a couple of notches.

 

[subaqua]

Have you adjusted the limit screws Pat.

I tend to look for youtube videos to try to help me, but I sometimes come unstuck

This seems to offer good advice

DO NOT ALTER LIMIT SCREWS UNLESS CHAIN IS FALLING OFF THE RINGS . it will cost yopu at least an hour of your time starting the set up procedure from scratch, from personal experience

techdocs on the shimano website - google techdocs or google SRAM techmanual if its SRAM kit. the set up and indexing instructuions are top notch.

 

[geopat]

Well turning the adjuster a couple of turns hasn't worked...I take it this just loosens the gear cable? Not sure how this can stop the rubbing. Anyone?

 

[qwiksilver]

is your mech strt?
if its rubbing at the rear of the mech or the front of the mech is your biggest clue to this as the chain will run strt if the chain is rubbing right in the middle of the mech then its a case of adjusting the tension and its a fiddly job.
turn your adjusters very slight to points on a clock if that make sense.
it took me only 30 mins today to change my d/t shifters to sti and adjust em practice makes perfect

 

[deptfordmarmoset]

Well turning the adjuster a couple of turns hasn't worked...I take it this just loosens the gear cable? Not sure how this can stop the rubbing. Anyone?

If you're talking about the screws on the front mech, then no, they don't affect the gear cable tension, they adjust the amount of travel the dérailleur has. A slight worry now is that if you've done 2 complete turns and it hasn't worked, you might have adjusted the inner limit instead of making the outer limit a wee bit wider. Before you try the bike out in anger, make sure you haven't adjusted it so that the dérailleur doesn't bury itself in your spokes on the first hill you come across. If that's what's happened, put it back where it was and give the other screw a quarter turn at the most to see if it cures it or, at least improves it. If it improves it, continue adjusting it but very, very gently.

Cautionary tale: I once bought a second hand bike in Sheffield. One mile into my journey home, I found myself needing to accelerate on a steep hill because of a lorry bearing down on me. Luckily the lorry missed me but the bike never went another inch with me on it - the dérailleur went into the rear wheel, wrecking the wheel, dérailleur and knocking the steel frame completely out of shape. It simply hadn't occurred to me that the bike was badly adjusted.

 

[geopat]

If you're talking about the screws on the front mech, then no, they don't affect the gear cable tension, they adjust the amount of travel the dérailleur has. A slight worry now is that if you've done 2 complete turns and it hasn't worked, you might have adjusted the inner limit instead of making the outer limit a wee bit wider. Before you try the bike out in anger, make sure you haven't adjusted it so that the dérailleur doesn't bury itself in your spokes on the first hill you come across. If that's what's happened, put it back where it was and give the other screw a quarter turn at the most to see if it cures it or, at least improves it. If it improves it, continue adjusting it but very, very gently.

Cautionary tale: I once bought a second hand bike in Sheffield. One mile into my journey home, I found myself needing to accelerate on a steep hill because of a lorry bearing down on me. Luckily the lorry missed me but the bike never went another inch with me on it - the dérailleur went into the rear wheel, wrecking the wheel, dérailleur and knocking the steel frame completely out of shape. It simply hadn't occurred to me that the bike was badly adjusted.

Apologies, I adjusted the barrel adjuster as the the YT clip above.

 

[Pat "5mph"]

Hi Pat, after watching the videos on you tube, reading the post on cchat, fiddling with the derailleur screws, front gears 6 and 7 were still grating. Took the bike to lbs, he fiddled for 10 min, all was good on the bike stand - which by the way I think one really needs one for this job, I only have a small rear wheel lifter, now gear 1/2 are grating!
Adjustments are obviously trial and error, take a lot of time.

 

[Scilly Suffolk]

This might help.

 

[deptfordmarmoset]

Apologies, I adjusted the barrel adjuster as the the YT clip above.

Phew! As you were then. You may find that you will have to give the outer limit screws a gentle tweak anyway though.

 

[qwiksilver]

what bike is the problem on and what type of gears?