monk

I probably should have searched longer for a previous thread on this but here goes . . . simply put, I have a 2006 Fuji Roubaix RC with a Truvativ 53/39 crank, Ultegra front derailleur, and Ultegra cassette. I'm always having to take it back to the LBS for routine adjustments, but would love to be able to do it myself. I have the stand, book, tools, etc. Seems that no matter what I do with cable tension, limit screws, etc. I always wind-up having the chain just touching the inside of the derailleur cage on when I'm in the lowest gear and the outside of the cage when I'm in the highest gear. For example, when it rubs on the outside while in the highest gear I check the bottom of the limit screw and it isn't even touching the part of the derailleur that would cause it come in. Is my cable tension too light? Should I back off on both limit screws so they're not touching anyting, turn the cable tension screw clockwise until it stops and then loosen the cable? It just seems no matter what I do I can't get it quite right. By the way, the derailleur angle/height seems okay. Thanks for any help.

freeranger

A little rubbing on the cage when you are in the innermost or outermost cogs on the cassette isn't all that unusual. Just look at it as a reminder that you need it's time to make a shift to a different crank gear(at least that's how I view it!) Also, your shifters should have a "half click" that allows for a little "trimming" which might help with the rubbing. A little rubbing does not necessarily mean that the der. is out of adjustment.

BikeWise1

Take a close look at where the cable attaches to the derailleur. There is a little metal bump just below the allen bolt that secures the cable. Does your cable go under it, or over it. It should go over it, since it's function is that of a fulcrum, but many folks (including less-than-clued-in shops) still think it goes under it. Check that out and let us know. It will drastically change the amount of travel if it's wrong...

HillRider

Great post and you beat me to it. This advice is so good it should be part of any Shimano FAQ list. I've "fixed" several fd shifting problems for others by making just this change.

If you look at the instruction sheet that comes with Shimano front derailleurs, the cable routing is shown just the way you describe it but the wording doesn't emphasize it. It should.

monk

Thanks! I did have this wrong at first but fixed it . . . goes over it now.

monk

I probably didn't explain myself well. I know about cross-chaining. I was referring to when I'm in the big cog in the back and small ring in the front and small cog in the back and big ring in the front. There shouldn't be any rubbing w/these combinations. But you're right, when you cross-chain trimming is usually necessary.

Al1943

Did that fix your problems?

When adjusting the low limit screw double check that the chain is on the smallest chainring and largest cog, and for the high limit big ring and smallest cog.

Before attaching the cable to the FD be sure the shifter is in the small chainring position, flip the small shift lever several times then pull all of the slack out of the cable, then attach and adjust tension.

Al

dbg

And I find front derailer tuning to be the most touchy. You can vary the height of the derailer, you can twist it around on the tube, you can have the cable improperly pulling (previous post on "over versus under"). And if you're just playing with other than perfectly matched components, it may be impossible to get it working acceptably no matter what you do. Rear der's behave much better. I guess that's why many folks just give up and go friction on the front.

BikeWise1

Great! Now, when you turn the inner limit screw counterclockwise, does the der. move inward? If it doesn't, there are 2 possibilities. It is bottomed on the frame, or the cable's too tight. Opening up the outer limit screw will not make the der. go further out, it only "limits" how far out it can go. Cable tension is what gets it done.

If this bike were in front of me, I'd first check to make sure the outer plate is absolutely parallel with the outer c-ring. All is for naught if this isn't done. Then I'd release the cable, and set the low limit with the bike in the small c-ring and largest rear cog so it clears the chain and makes no noise when turning the cranks. There is a fine line between "no noise" and "chain drops onto BB shell". Next, attach the cable. While turning the crank by hand, shift down to the smallest rear cog and then pull down on the fr. der. cable in the middle of the downtube. Careful-if the upper limit screw is opened too far, you'll overshift and possibly scratch the crankarm. While holding tension on the cable, set the outer limit screw so that the outer cage clears the chain. Again, a very fine line between "no noise" and "chain falls off to the outside". Now, use the lever and shift onto the big ring. You may need to add a little tension at the adjusting barrel for this to work well, assuming the limits are set correctly.

monk

Thanks for everyone's input; without going into alot of detail, several of you have mentioned things I didn't do . . . will make sure I get it right the next time. For this time, I took it to my LBS because it's a new bike and it was ready for a free 30-day tune-up. But, naturally I want to learn how to do this myself. I'm getting there . . .

barok

hi, i'm having the same issue as the op...does anyone have a picture/diagram (or can point me to one)...i'm slow to visualize this ...tia

robhunterx

Hi barok:
This should be very helpful for proper FD setup:
https://www.parktool.com/repair/readhowto.asp?id=75

Steev

Try this.
https://www.parktool.com/repair/readhowto.asp?id=75

Beat me to it!

barok

thanks for the reply...but i'm actually looking for a pic/diagram on how the cable is supposed to be attached to the fd as bikewise1 had described it.

HillRider

I went to the Shimano web site and found the installation instruction .pdf for a typical front derailleur. It shows the correct way to route the cable if you look very closely but it is by no means obvious.

I'll try to repeat what bikewise described and maybe be a little more specific.

Look at the derailleur's cable fixing bolt from the rear of the bike. At about 7 o'clock, there is a small metal tab right next to and parallel to the bolt head. The cable must be routed so it goes to the left side (toward the frame) and above the upper edge of this tab before being run under the bolt head in the groove in the operating arm. The cable must NOT be run between the tab and the bolt.

I hope this is clearer.

barok

thank you much! i just went down to the garage and checked the cable & it was routed BELOW the tab ... i'll reroute it tomorrow after work (would have done it now but it's already late and it's freezing down there)...thanks again man!

tellyho

The thing I always have to remember when I'm adjusting my front derailleur is cable stretch. If you adjust cable tension, make sure you move that derailleur back and forth a couple of times before taking it out for a ride - it takes a bit for the system to settle into the final tension at which it is going to work.