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Nooooo!!! It Doesn't Work!!! Help!!!!!(6 posts)

Nooooo!!! It Doesn't Work!!! Help!!!!!wilier
Sep 12, 2003 6:32 PM
Please help if you have a similar set-up or if you have knowledge to what my problem is.

Shifters: Ultegra STI Triple
Rear Derailleur: XT
Rear Cogs: Ultegra 9 (12-27)
Front Derrailleur: LX Top Pull (on a MTB Hard-tail)
Front Crank: Really old triple (22-32-42) soon to be upgrade when I have money.

The Rear is shifting beautifully.

The front is giving me major problems. It seems to me that the throw on the Ultegra is not sufficient to match the required throw on the LX front. In other words, the Ultegra STI's simply are not moving enough cable to get me either to the small ring or the large ring. I know that the stop screws are ok because as I adjust the cable tension, I can shift either the small and middle ring, or the middle and large ring, but never all 3 at the same time.

This is my first experience with an indexed triple. Mostly I'm 2X in front and the last mountain bike I had was from 1991 with a friction front. I never had to deal with indexing to the middle.

Thanks!!
re: Nooooo!!! It Doesn't Work!!! Help!!!!!gbecker
Sep 13, 2003 4:30 AM
You are correct in your evaluation (in regards to the amount of cable pull). Shimano STI levers/ road front derailleurs and Shimano mtb shifters/ front derailleurs do not operate the same in this regard. Try this....Change the possition where your front derailleur cable is clamped (move it from "behind" the cable clamping bolt to "in front" of it). I have not tried it with a top pull fd before but I have done this on a bottom pull LX front derailleur and it works much better. Try that, post your results and we'll go from there.
Great suggestion - need a little more thoughwilier
Sep 13, 2003 4:15 PM
Thanks gbecker.

I moved the cable connection as you said - basically moving the cable closer to the actual pivot point. If I'm in a perfect position for the middle ring, I can get it to shift to both rings by hand pedaling the granks - Shifts are very slow and hard to get. I need maybe 1mm more movement either way. If I'm sitting there and applying any pressure, I can't get any shifts at all. Not sure why this is.

Other newly identified problems:

I learned a new thing today - I have a top pull, top swing. Don't know if this makes a difference. Someone told me to get a top pull, bottom swing. Don't know why this would be different.

It's also a 2001 front derailleur. Looks like it was meant to take a 44 or 46 large ring. I can only get it about 3mm away from the big ring when it passes it. Usually I'd set it as close as I can get it without making contact. If I get any closer, the front derailleur will hit the chainstay in the granny shift.

As noted previously, I have a really old crankset that may have to be replaced sooner than later. The rings have no ramps and pins to assist in shifts to a larger chainring. Perhaps this will help a little.

Thanks!!

-Wes
9speed vs 8speedAtombomber
Sep 14, 2003 12:43 PM
If you have a crank designed for 8speed drive train, it might be a bit wide for use with a 9speed chain. The spacing is a tad tighter on the 9spd to compensate for the narrower chain and the front deraileur is designed to work harmoniously. If possible, see if you can bowwow a similar 9speed crank to see if it improves your situation. If it helps, problem solved and lighter wallet.
prev post - a bunch of guys said this would workwilier
Sep 13, 2003 4:32 PM
wilier "Really convoluted CX bike design" 8/20/03 6:17pm
STI Levers/MTB ringshaimish
Sep 13, 2003 6:43 PM
As usual, Sheldon's got info on this. From http://sheldonbrown.com/harris/derailers.html#front
Shimano fronts use a different amount of cable pull for drop bar vs straight bar controls. This makes it difficult if you want to use a "road" crankset, with full-sized chainrings (52, 53 top) with straight handlebars, or if you want to use a "mountain" crankset (44-48 tooth top) with drop bar STI shifters.

He sells a "problem solver" NOS front mech that apparently was designed for a setup like yours-looks like they're bottom pull, though.

Another (more costly) solution: Ergo levers-works with any front deraillleur/crank setup. Or of course you could go the Lance route and use a DT or barcon friction shifter for the front.