Bicycle Mechanics - Ultegra Front Der with 44-32-22 Crankset?

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Cyclesafe
09-14-10, 07:47 AM
I want to use drop bar shifters (Ultegra 10-sp STI) with a 44-32-22 crankset (Raceface Deus).

Would an Ultegra front derailleur work? Do I need to get a new Ultegra 6700 (10-sp) front derailleur or would my existing Ultegra 6500 (9-sp triple) front derailleur suffice? Will either work with a large chain ring of only 44 teeth?

I've been happy for 35k miles with the latter and a large chain ring of 46 teeth....

Thanks in advance for your help!

Retro Grouch
09-14-10, 08:19 AM
It's going to look a little goofy with that small chainring but I've never tried it so I honestly don't know.

Since you already own it, why not try it for yourself and see if you can make it shift to your satisfaction?.
HillRider
09-14-10, 07:18 PM
Road front derailleurs intended for 50 - 53T large chainrings do seem to shift decently with smaller "big" chainrings as long as you position them suitably close to the ring's teeth.

Shimano's old RSX triple cranks came with 46/36/26 chainrings and used an RX-100 front derailleur intended for a full size 52/42/30 road crank. It shifted quite well.

Bezalel
09-14-10, 07:37 PM
Front derailleurs don't have a minimum sprocket size, just a maximum size. It might look weird but you dont really have any other good options. MTB front derailleurs won't work with road indexed shifting.

You might get smoother shifting with a 10 speed derailleur.
Shimagnolo
09-14-10, 07:56 PM
Here is an Ultegra 6503 FD with an XT 22/32/48 crankset.
(The 48T chainring is from the "trekking" set.)
It does work, but the shifting from the 32T -> 48T is nothing to brag about.

http://www.dim.com/~ryoder/SomaPhotos/IMGP0018.jpg

The photo is deceiving.
The curve of the cage does not follow the chainring very well.
The result is the trailing end of the cage is quite far from the chainring, making the middle-to-large shift sloppy.
Bezalel
09-14-10, 08:16 PM
Here is an Ultegra 6503 FD with an XT 22/32/48 crankset.
(The 48T chainring is from the "trekking" set.)
It does work, but the shifting from the 32T -> 48T is nothing to brag about.


That might have something to do with the rated capacity of the derailleur. The total capacity is 22 teeth and the max differeance between the top and middle is 13 teeth.