Chain rub help!

SpainSte

Hi all,

When I am riding along I get a lot of annoying chain rub, all on the big ring and on the highest gears (the smaller cogs). I have tried to turn the adjuster screw (looking down from the saddle, the one nearest the chain rings) but it doesn't actually make any difference, there is no movement of the derallieur no matter how much I tighten or loosen the adjuster screw. I can however hold in the shifter which forces the derallieur out a couple of millimeters and that stops the rubbing but clearly I can't ride like that all the time. I have a feeling this is something small so I dont want to have to go to the LBS if it is something I can do myself.
I have Ultegra components on a Focus Cayo.

Does anyone have any suggestions?

Thanks in advance!

arlowood

You've sort of answered your own question in that the rubbing disappears if you apply some extra pressure to the STI lever.

This indicates that you need to apply a bit more tension to the cable by means of the downtube or in-line barrel adjuster. With the chain on the big ring and smallest rear sprocket, spin the cranks and turn the barrel adjuster anti-clockwise maybe half a turn at a time and hopefully this will move the FD cage sufficiently to eliminate the rubbing.

If that doesn't work then I suggest you go back to basics and do a full set up on the FD. This video is a pretty good guide IMHO

http://roadcyclinguk.com/how-to/mainten ... lleur.html

SpainSte

Thanks for the reply!

Just done this and hey presto, problem solved. I wrongly believed that the adjuster screw would move the cage inwards or outwards, but it didn't, adjusting the cable tension solved the problem straight away.

Thanks again for your help!

rafletcher

If your front mech is properly set up you never need an inline adjuster.

sigorman85

Well it's obviously not ....I have the same problem with my 105 set up if I had a few hundred spare at the moto would up grade it I hate it ....

desweller

rafletcher wrote:

If your front mech is properly set up you never need an inline adjuster.

Same argument can be applied to the rear derailleur. It's a question of skill and how long you're prepared to spend fiddling around with the clamp screw.

The adjusters are there to make life easier.

sigorman85 what exactly is the problem with your 105?

fudgey

Be warned that now you have adjusted the upper and lower limits of the front mech that it may now push the chain off on up shifts and down shifts if the mech can move too far in either direction.

philkeeble

I had this problem with the Ultegra-equipped Roubaix I purchased at the beginning of the year. It went back to the shop a couple of times and didn't get fixed. I never knew if it was fixed at the 3rd attempt because by that time I was so fed up with the recurrent clicking BB30 bottom bracket (and Specialized's recommended fix of epoxy gluing the bearings in place!) that I took a full refund. I suspected that the cable converter was fitted wrongly. Curiously the next bike I bought (with threaded bottom bracket, incidentally) also had a rubbing issue but it came with the special Shimano alignment tool (TL-FD68) that allowed me to check the cable converter. Lo, it was installed wrongly. After refitting the right way round and readjusting, all was well with the world.

Not a lot of folk know about this cable converter on the 11-speed Ultegra. It didn't exist on the old 10-speed series, and doesn't get a mention on the user section of the Shimano support document site; it's only on the dealer's section where all is explained in the full installation guide. It's worth checking out.

See http://si.shimano.com/#seriesList/38/50 , look for document DM-FD0002-04 in the FD-6800 section

Bobbinogs

Fudgey wrote:

Be warned that now you have adjusted the upper and lower limits of the front mech that it may now push the chain off on up shifts and down shifts if the mech can move too far in either direction.

Yepp, Shimano FRs are designed to overshift to a small degree as that makes the shifting better/faster. The trick is to set the high stop to the right place when in Big (F)/Small (B), as in just about 0.5 to 1 mm of clearance. When shifting, keep the action smooth using a shift/release action whilst pedaling. If one holds the lever too long at the max extent then the chain can drop off (however, this can usually be recovered by releasing the lever and gently pedaling).

Oh, and don't forget the trim feature. It is amazing how many club riders simply don't know about the trim feature on the FR. Using inline adjusters really help getting the right balance on trim and avoid flatting a cable due to constant try it/adjust it/try it of the cable clamp to get the main shift and trim both right.