Front derailleur problems/adjustments

[Mushroomgodmat]

Hi,

So I fitted my own groupset - generally speaking everything is working fine apart from my front dérailleur.

Please see image

I think its fairly obvios what the problem is, as I change the gears at the rear the angle of the chain changes (obviosly) and rubs the front dérailleur as a result. This is Ill admit easy to fix if I just change gears at the front as it moves the chain into a clear position. Also, the rubbing is fairly minor, but Im assuming any rubbing is a bad thing?

My other problem is no matter how I adjust the cable, Its maybe 2 (or even 3) times harder to use the shifter for the front dérailleur than it is for the rear. The rear dérailleur works like a dream, which I have found to be super simple to setup.

Its posible both of these problems are normal and expected, but if they are not could someone let me know how to fix it. Assume I know nothing!

BTW, the group set is shimano 105

 

[Pauluk]

Are you using an extreme combination of gears. Large rear large front cogs?

 

[citybabe]

have a fiddle with the height and angle of the derailier on the seatpost . I changed my chainset a while ago and that is what somebody on here told me to do and after a while I managed to sort it out

 

[boydj]

It is almost impossible to avoid chain rub when you are in the extreme gears - large/large or small/small, particularly with a compact chainset - and frankly, you should not be using these gears. When you are on the large ring, you should avoid the two lowest gears at the rear, and similarly from the small ring it's best to avoid the two highest gears. This will mean changing between chainrings more often than you might want on undulating roads.

Getting the front mech set up properly can be tricky. It needs to be as low as possible while still not hitting the large chainring. You may need to play about with the positioning to find the optimum angle which should be close to parallel with the chainrings, but maybe not exactly so.

 

[subaqua]

what make and model front derailleur ?

as others have said large front/small rear and small front/large rear should be avoided. generally rou need to set it up so the bottom of the carrier is about 1-3mm above the large chainring and parallel with the chainring. it can take a while to get it set up but its worth spending the time.

http://techdocs.shimano.com/techdocs/index.jsp


http://www.sram.com/service

are really useful places for detailed set up and troubleshooting info

 

[Mushroomgodmat]

cheers for the advice guys, you confirmed what I thougt!

Odd question though, Iv set up and adjusted my from dérailleur now (working fine) but now I have a creaking sound as I change gears (front gear) - its like there is too much tention in the cable and its putting too much force on the shifter - the noise is comming from inside the shifter!

 

[Mushroomgodmat]

Forget about the creaking - it was a combination of me over extending the movement in the front derailleur. The noise was not comming from the shifter, but from under the frame where the cable runs round to thr derailleur. Added some grease, lowered the minimum/maximum movement and it seems to have gone away.