casjr2171

I have searched this thread multiple times with no hits, so I'm going to ask for the collective wisdom of this forum before I take my bike back to the mechanic who did the work. Here it is: I had my guy at Performance install a (OK, used) Ultegra 6600 front derailleur to complete my all-Ultegra 6600 drive train on my 2011 Felt Z6. It didn't make sense to me to have everything 6600 except for the remaining 105 front DR, despite the fact that I know there is little, if any difference in the 105 and Ultegra components.

My first ride today, I tried shifting chain rings just to check things out. I had to stop, flip the bike, and manually move the chain from the small chain ring back to the big one. It just wouldn't shift up to it. When I came home, I put the bike on the wall rack and tried shifting small to big and found that if I shifted the lever 3 times, sure enough, the FD moved the chain from the small to the big ring! But why 3 shifts of the lever???

Granted, I should go right back to Performance and have the guy set it right, but I find that I learn so much when I ask questions here that I felt it would be good to at least ask about it.

So what say you? (And many thanks in advance)

fietsbob

105 costs less than Ultegra , they both shove the chain sideways with the same principles .

I'd have to watch in person to know what you are talking about..


<guess> is there too much slack in the cable when on the small chainring?
might have slipped thru the clamping point on the FD. bolt not tight enough.

Al1943

If you have a double crankset there should be no difference in the shifting performance. You should always be able to shift from the inside ring to the big ring with one full sweep of the lever. If you have a triple crankset there are differences in the FD's to match the differences in ring sizes. In any event if the crankset, shifters, derailleurs, and chain are all 6600 it should shift perfectly.
Not sure but it sounds as if there is something wrong with the setup.

caloso

I was also going to guess a slack cable.

And although you didn't ask, there is no reason to replace a 105 FD with Ultegra other than being able to say your bike is all-Ultegra. But at least now you have one more component to throw into the spare parts bin from which you can eventually build a rain bike or CX bike.

bikeman715

You can have slack in the cable , but it could also be flex in the frame ( most so in the bottombacket ) causing the derailleur not to shift right . You may also have some friction in the housing which will keep the cable slowing down or stop it from moving right . Your crankset might be loose and flexing as you pedal . You did say the derailleur is used and maybe it just worn out .

Camilo

I'm not going to make any unsolicited comment about 105 vs. Ultegra since you actually explained very well why you did it. I think wanting a full (whatever) drive train is a perfectly fine reason to upgrade a component. I mean, the tired old "105 vs Ultegra" debate could be made for every single component on the drive train. I would have done the same thing you did without hesitation.

That said, the shop should be able to easily and quickly fix the shifting and there's no reason - other than time and hassle - not to bring it to them and insist they fix it to your satisfaction while you wait.

On the other hand, FD adjustment sometimes just takes some tweaking. It can actually be kind of fussy. But it is an excellent thing to learn to do yourself. No special tools required, and once you get the hang of it, the tweaking becomes intuitive almost and it will be easy and efficient to take care of it yourself.

Andrew R Stewart 

The OP says he shifted the ft 3x before the chain climbed onto the large ring. Are we to assume that the lever has three strokes of movement? Or that you released back to the small ring's position and reshifted?

Likely the unsaid second choice. So, what did you do differently the third shift. Move the lever ALL the way? Hold the lever until the chain climbed up? Softened the pedaling force? Quickened the pedaling speed? Andy.

brianmcg123

Those two smaller "shifts" are trimming positions. If you make one big shift it will shift. But shift it like you mean it, not a little nudge.

catonec 

+1

-1 on the frame flexing theory (sorry bikeman)

Andrew R Stewart 

I added "full" to my post for clarification. Andy.

AnkleWork

Why not reinstall the 105 and put an Ultegra sticker on it?

catonec 

the problem is not w/ the deraileur, its in the cable or setup.

dbg

+2. These may be trim positions you are mistaking for shift positions. Full push and brief hold.

leob1

It's easy to tell if it's the cable set up; shift to the small ring, then try to shift it again. Have a look at the cable and housing, there shouldn't be any slack in the cable, or the housings should not move out of the stops. If there is then the cable is too loose. Also the low limit screw might be set too low, this will make the derailleur have to move too much before it starts to shift. These can be all small amounts of slack in the system, but when added to the trim positions of the shifter, it will mean sloppy shifting.
Take it back to the LBS for an adjustment.
BTW 10 to 1 they will tell you it was 'cable stretch' that caused the problem.

caloso

So how does the OP fix this? Get a 5 mm hex wrench and a pair of pliers or vise-grips. Put the lever in the lowest position, loosen the pinch bolt, pull the cable taut, tighten the pinch bolt. Then test it out.

Delmarva

Before the op fixes or adjusts anything, as mentioned above he should try shifting using a full throw of the shifter. He may in-fact be making trimmer movements of the shifter. If that doesn't work it's back to the lbs to have them make any adjustments or fixes.

AnkleWork

The 105 worked.

caloso

Before it was uninstalled. I think the working theory here is the installation of the new FD, not the FD itself.

casjr2171

I think I have found the problem . . . the shifter itself is at fault. After more LBS adjustments, it shifted OK for awhile until it started "skipping" entirely when I attempted to shift small back to big ring. That is, I could push the lever -- all the way -- over and over again and it was if there were no cable attached to it at all. I have to repeatedly until finally, it catches the cable and makes the shift. It could mean half a dozen attempts before the shifter grabs the cable.

Am I wrong or does this sound like my left shifter is ready for the junk pile? Is it worth trying to get it fixed and who can rebuild one? I'm doubtful that my local mechanic does that kind of work.

RoadTire 

That is a really odd coincidence - all was working perfectly until the FD was changed, a couple trips to the LBS, and now the shifter is acting up? I would start over, throw the 105 FD back on the bike before replacing any more components. Wunderground says it's 38 deg in Richmond, any chance temperature is slugging up the shifter?

bikeman715

Yes temperature can affect the hardest of the grease and make the shifter misfire or not shift at all . spray some WD-40 into the shifter to soften the grease as moving the shifter . Once moving add some light oil like Triflo to it .

alex jb

Did they change nothing else?

I had a problem a while back where purely time and cable tension started to pull the outer shift housing wires through the cheap end ferrule, something to check for.

bikeman715

+1

casjr2171

Many thanks for all the advice. Once again, I have learned the amazing curative powers of a good cleaning flush and lube. While still not perfect, I realize my older 6600 STI shifters are somewhat worn. When the left one fails to shift, it feels just like a worn ratchet wrench that doesnt fully engage and "catch" the ratcheting mechanism. I'm still playing with cable tension a little, but it works much better after the clean and lube.