Bicycle Mechanics - Need help with Shimano XT front derailleur

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Ali_baba6666
01-28-07, 03:04 PM
I have a K2 bike which has a top route type frame. Couple of days ago I got a new XT front derailleur which I want to put instead of my Deore. The problem is that the new derailleur is a bottom pull and it is not compatible with my frame. My question is if there are any adjustments to the frame or the derailleur which I can do so I can install the XT, and if there are, are they gonna decrease its performance. I personally prefer to keep the top pull if it is possible because I’ve read that this way the cables are preserved better.
I am open for any tips and suggestions.
Thanks!


oldSkoolXC
01-28-07, 03:36 PM
As far as I know, I'm about 99% sure that you must use the derailleur type that the frame is set up for, i.e. top pull or bottom pull.
There is no way that I know of to make one work in place of the other. You pretty much have to stick with what the frame dictates.

Proximo
01-28-07, 04:45 PM
I have a K2 bike which has a top route type frame. Couple of days ago I got a new XT front derailleur which I want to put instead of my Deore. The problem is that the new derailleur is a bottom pull and it is not compatible with my frame.

All of the current XT front derailleurs can be used with either top or bottom cable routes (Shimano calls it "dual-pull"). Look at the instructions carefully.


oldSkoolXC
01-28-07, 04:46 PM
All of the current XT front derailleurs can be used with both top and bottom cable routes. Look at the instructions carefully.

I guess I just dated myself. I didn't know that.

Proximo
01-28-07, 04:53 PM
If you look at the cable fixing screw, it's attached to a cam plate that has a half round cable guide milled in the edge of it. The cable comes up from the bottom, wraps over and around the cam plate cable guide and attaches to the bolt. When using with a top pull, the cable just comes straight down and attaches to the bolt.

edit: Shimano has three different XT front derailleurs, the FD-760, FD-760-E and FD-761. The 760 and 761 have different style bolt fixing plates but the idea is the same. For bottom pull, the cable wraps around the plate to reach the fixing bolt.

Ali_baba6666
01-29-07, 09:37 AM
Thanks for the advices but I am guessing that I have an older version of XT (by new i meant not used) because mine as far as I can see there is no way the cable can come from above and attach directly to the bolt because it wont pull in the right direction. It has to go underneath, wrap around and then attach to the screw bolt, but there is no cable guide which to guide the cable if it comes from above. There is only a cable guide right under the screw bolt which is made to guide a cable coming from the bottom and it is pretty short one (it doesn’t go all the way around). I took couple of pictures you can see what I mean. The first one is the top where the screw bolt is and you can see the cable guide. The second is bottom and as you can see there is no cable guide there for the cable to wrap around.

Proximo
01-29-07, 10:22 AM
It's kind of hard to tell the orientation from those pictures but that looks like an older version of the M760, low mount, derailleur. I have one of the new ones and the fixing bolt is almost horizontal to the ground (perpendicular to the seat tube). That allows you to come up from underneath and wrap over the bolt plate or to come from the top and connect directly to the bolt. Yours looks like the bolt is pointing down at the ground so you have to wrap the cable for it to work.

You should be able to get a new one on ebay for $25-35.

Ali_baba6666
01-29-07, 04:49 PM
On mine the bolt is almost parallel to the seat tube. But there is no way I can put the cable underneath and if I put it directly from the top it is not going to pull b ut just getting loose. I hope on those picture you can see better

Proximo
01-29-07, 08:01 PM
Those pics are much better. It's very different from the new ones. The bolt points up so you have the same issue if it pointed down. It is definitely bottom pull only. You'll need to get a new one for top pull.