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-   -   Front derailleur cage too narrow? (https://www.bikeforums.net/showthread.php?t=1175812)

cyclingman1 06-16-19 11:46 AM

Front derailleur cage too narrow?
 
Had a bike store upgrade my older Cannondale to 11 speed Ultegra, double. They cannot seem to adjust the front derailleur where there is not chain rub on big chain ring regardless of which rear sprocket is being used. The trim operation is only minimally effective. In looking at the front derailleur, it appears very narrow with indentations on the inner side of the cage on each side. The cage on my 2010, 10 speed Trek Madone has to be at last twice as wide - no issues with it. The derailleur has "Eclipse" on the tube clamp. I'm assuming they used the correct derailleur. I'm puzzled by this. Never had a front derailleur that could not be adjusted in over 40 yrs of cycling.

dsbrantjr 06-16-19 12:50 PM


Originally Posted by cyclingman1 (Post 20981469)
...I'm assuming they used the correct derailleur. I'm puzzled by this. Never had a front derailleur that could not be adjusted in over 40 yrs of cycling.

Might be a bad assumption. Is the derailleur suitable for the crankset's number of teeth on each chainring? The indenations must line up with the chain positions within fairly close limits. If there is too great a difference what you are describing is likely to occur. The derailleur cage must also be parallel with the chainrings, also within pretty close tolerance. All of these things are a lot more finicky with 11 speeds than with earlier 10-9-8-7 speed parts.

fietsbob 06-16-19 01:06 PM


Never had a front derailleur that could not be adjusted in over 40 yrs of cycling.

my 40 year old friction shifted driver trains continue to be so.. :50:


but you wanted your bike to have the latest parts , namely an 11 speed drivetrain ..

Andrew R Stewart 06-16-19 02:45 PM

I highly doubt that the 11 speed cage is really half the width of older examples. Andy

shelbyfv 06-16-19 03:59 PM

If you will take the time to post the model numbers of your FD and crank you'll get better feedback.

blamester 06-16-19 04:31 PM

So it rubs in the when in the middle of the cassette?
Check the FD is parallel with the chainring.
It ain't rocket science.

cyclingman1 06-17-19 02:45 PM

Was able to find a really good bike mechanic at a place in N. Ga that I had never been to. Been a mechanic for nearly twenty years including work in Europe as a team mechanic. His findings, observations, and actions: Yes, the 11 speed FD is considerably more narrow than is the 10 speed. There is a hard plastic cage edge that suggests that a certain amount of chain rub is expected. Virtually every adjustment of my FD was off a little. I now have a couple of more gears with no rub at all. This FD makes using the small CR imperative if one does not want rub when going to large sprockets. I'll try this for a while.

fietsbob 06-17-19 03:45 PM


the 11 speed FD is considerably more narrow than is the 10 speed.

So is the 11 speed chain..

cyclingman1 06-17-19 06:17 PM

Not by the same percentage. I have both. The 11 spd chain is "slightly" smaller. The 11 spd FD has indentations on the cage sides that really accentuates the smaller opening.

jadocs 06-17-19 06:27 PM

Something is off. It should not rub with the probable exception of cross chaining (big ring big cog, or small ring small cog)...if the FD is properly aligned and the limit screws are adjusted accordingly.

Phil_gretz 06-18-19 09:20 AM


Originally Posted by cyclingman1 (Post 20983381)
...Yes, the 11 speed FD is considerably more narrow than is the 10 speed. There is a hard plastic cage edge that suggests that a certain amount of chain rub is expected. Virtually every adjustment of my FD was off a little. I now have a couple of more gears with no rub at all. This FD makes using the small CR imperative if one does not want rub when going to large sprockets...

Numbers do matter. Are we talking FD-6800 or FD-R8000? And the crankset? And the shifters? It's possible to predict the behavior [of your new combination] by simply knowing what parts are involved, their compatibility and their spacing.

cyclingman1 06-18-19 10:32 AM

I don't think this forum is intended only for bike part gurus, expert mechanics, or the like. I had/have a problem, made some minimal observations, and posted. There was/is no implication of being an expert on bikes or being capable or wanting to argue with aforementioned bike gurus. I am/was simply looking for basic help.

There are no part numbers on the FD that are obvious. It says "Ultegra" on the cage and "Eclipse" on the clamp. I have not and am not going to disassemble the bike looking for part numbers. As far as cranks, I know they are 175mm and are 50/34. Yes, I tend to ride cross-chained: big CR and bigger sprockets, although not the largest. I also do that on my 10 speed Madone. Never hear a sound. My new-found mechanic says that one cannot get rid of all chain rub with my parts. Although, if I do a lot of shifting between CRs, most of the rub disappears. That is highly inconvenient because shifting to small CR necessitates a multiple shift in the rear to get the same gear ratio - a real PITA. The mechanic helped a little. Did 25 mi this morning with tolerable results. May still consider replacing 11 speed FD with 10 speed FD. I think it would work. My Madone is a 50/34 and the amount of lateral travel is the same for the FD.

Delmarva 06-18-19 10:59 AM


Originally Posted by cyclingman1 (Post 20981469)
Had a bike store upgrade my older Cannondale to 11 speed Ultegra, double. They cannot seem to adjust the front derailleur where there is not chain rub on big chain ring regardless of which rear sprocket is being used. The trim operation is only minimally effective. In looking at the front derailleur, it appears very narrow with indentations on the inner side of the cage on each side. The cage on my 2010, 10 speed Trek Madone has to be at last twice as wide - no issues with it. The derailleur has "Eclipse" on the tube clamp. I'm assuming they used the correct derailleur. I'm puzzled by this. Never had a front derailleur that could not be adjusted in over 40 yrs of cycling.


Originally Posted by cyclingman1 (Post 20983381)
Was able to find a really good bike mechanic at a place in N. Ga that I had never been to. Been a mechanic for nearly twenty years including work in Europe as a team mechanic. His findings, observations, and actions: Yes, the 11 speed FD is considerably more narrow than is the 10 speed. There is a hard plastic cage edge that suggests that a certain amount of chain rub is expected. Virtually every adjustment of my FD was off a little. I now have a couple of more gears with no rub at all. This FD makes using the small CR imperative if one does not want rub when going to large sprockets. I'll try this for a while.

It should be narrower but a proper alignment and adjustment should permit all combinations to be accessed. I cannot imagine an Ultegra or any other model was designed for chain/cage contact other than when shifting. Something missing here. Is there any damage? Were the correct components used?

alcjphil 06-18-19 11:56 AM


Originally Posted by cyclingman1 (Post 20984559)
May still consider replacing 11 speed FD with 10 speed FD. I think it would work. My Madone is a 50/34 and the amount of lateral travel is the same for the FD.

No, that will not work. Ultegra 11 speed front shifters pull more cable than the older 10 speed ones did. A 10 speed front derailleur won't match except possibly for a Tiagra 4700. One question: does your Cannondale have shorter chainstays than your other bike? Short chainstays can make front derailleur setup more difficult

Phil_gretz 06-18-19 12:47 PM


Originally Posted by cyclingman1 (Post 20984559)
...There are no part numbers on the FD that are obvious. It says "Ultegra" on the cage and "Eclipse" on the clamp. I have not and am not going to disassemble the bike looking for part numbers. As far as cranks, I know they are 175mm and are 50/34...

The FD part number is stamped onto the backside of the inner cage, readable from the non-drive side. The STI shifter part numbers are molded into the shifter body, beneath the hoods. The crankset numbers are (likely) cast into the inner side of each crank arm. Or, ask your mechanic. He will know the part numbers by observation.

cyclingman1 06-18-19 01:14 PM

Cannondale R 1000, Blk, Grn, Yel, 2004. Short chainstays. About 1/4" clearance for tire next to seat tube. As far as more cable pulled by 11 spd shifters, it would seem that the stop [H] would take care of that?

alcjphil 06-19-19 08:10 AM


Originally Posted by cyclingman1 (Post 20984827)
Cannondale R 1000, Blk, Grn, Yel, 2004. Short chainstays. About 1/4" clearance for tire next to seat tube. As far as more cable pulled by 11 spd shifters, it would seem that the stop [H] would take care of that?

The derailleur would hit the H stop before the shifter clicked into gear


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