Sorted Front derailleur advice

m88arx · Jul 20, 2012

Basically on the gt lts 3 i have i was going to put on the xtr 961 fd i bought but its not working the chain is actually resting on the mech, so found the stx rc one that came with it and worked ok. I wanted to upgrade it thou i have found an xt fd-m751 top swing bottom pull, the first one on the techdoc looks the same as the STX RC FD I have but was wondering is there an xtr alternative please with the same build as the STX one aswell as the XT one.
Chainstay angle is 66-69 degrees
Oh forgot to put am running 9 speed so wasnt sure to put it here or the 98> forum
Thanks in advance

Tech Doc FD-M751 http://techdocs.shimano.com/media/techd ... 611893.pdf

Anthony · Jul 21, 2012

It came originally with an STX top-swing, bottom-pull. Your photos show conventional-swing, bottom-pull mechs, but there's no reason why conventional-swing mechs shouldn't work. Some LTS models had top-swing, some had conventional-swing.

Yes, all XTR mechs would be available in either top-swing or conventional swing, but as I say, either should work.

On my full-suspension bike, the chain rests on the mech cage and makes a hell of a noise when the bike is on a stand, but when I'm riding it, the sag takes the cage below the chain. Is it possible that's what you're experiencing? I think the 66-69 degree angle is pretty standard.

m88arx · Jul 21, 2012

Ok and thanks for the advice this is what i have the top two are the original on the granny ring in 9th gear. The one on the bottom is the fd-m961 xtr i bought thought would be nice, but like you said rests on the derailleur. I hear what you say about the rear suspension being pushed down and then it wont rest on the derailleur. But for argument sake you wouldnt got to your lbs and buy a bike like that, which is what i have kinda said to myself so there must be a fix for this or i may just have the wrong derailleur. Sorry for my inadequate knowledge on these conventional and top swing derailleurs.

Top two pics FD-MC32
Bottom pic FD-M961

cheers
Marc

hamtaro145 · Jul 22, 2012

the answer about sag is a good one, but it could also be that the FD is not designed for the angle of the seat tube of his bike. somewhere on the FD (well they used to) it will have stamped the range of degrees it is designed to operate properly within. one of my Xt ones has 66-69 degrees on it.

gtRTSdh · Jul 22, 2012

m88arx":15z4dzqq said:
Top two pics FD-MC32
Bottom pic FD-M961

You can see in the pictures that the cage of the old front mech follows the radius of your chainring (42T I guess) much more closely than the XTR version. This normally indicates that XTR front mech is designed for a bigger front chainring such as 46T/48T, the fact that your chain rubs where it does also suggest that the XTR mech is intended for a double not triple crankset. 29T/44T I think for MTB chainsets which would meake the chain higher than if it were resting on a 22T granny.

See here for the very clear differences between a double and triple front mech inteneded for road bikes.

http://sheldonbrown.com/front-derailers.html

m88arx · Jul 23, 2012

Picture of the xtr front derailleur
http://www.retrobike.co.uk/forum/viewto ... t=#1574543

I was looking for a xtr Fd to go with what I have but i saw this one and thought it looked nice

I have
RD XTR FD-M952
V'S XTR M951

Chainstay angle on the back is 66-69 degrees which seem to be alot of FD's are

Saw this one on the bay from over the pond it is an XT one but thought if there is an XTR one similar

http://www.ebay.co.uk/itm/Shimano-Deore ... 231fe2bc6b

It looked relatively similar to the STX one I have

Thanks In advance
My headaches seem to get so much worse when i thin about FD'S at the mo

Marc

hamtaro145 · Jul 23, 2012

now i think about it (especially after seeing your latest pic) i have had an Fd do the same thing years ago...think i ended up getting a new fd designed for compact size rings, thats probably why i have 2 spare old school Xt Fd's sitting in my box of bits!

FluffyChicken · Jul 23, 2012

Of course there is an XTR mech.
From M95x series on they made top and bottom swing mechs in the series even until today.

Try M953 if wanting bottom swing '9 speed'

But the cages should be similar between the types.

That M961 one you have is a compact triple design, so 44T* max. and pretty much like all others. in fact a bit more capacity than the 42T of the MC32 so should be easier to set up

*often labelled as 42/44T

m88arx · Aug 20, 2012

Update

Still having probs couldnt find an xtr mech that worked after another xtr failure i bought one from dead rats but didnt work my fault but nevermind
i bought an xt from a mate happened to be new so thought great. Still stuck with my stx fd mc3. Tried this one one and was still resting on the derailleur but have noticed the cage and its curve as in pic below. Starting to think an 8 speed xt front mech would do, would this work on a nine speed set up

P.s they been set up right and this xt was my fifth mech i tried

m88arx · Aug 24, 2012

Sorted with a Shimano M751 bottom pull bottom swing

Marc

Sorted Front derailleur advice

m88arx

Retro Guru

Attachments

Anthony

m88arx

Retro Guru

Attachments

hamtaro145

Dirt Disciple

gtRTSdh

Senior Retro Guru

m88arx

Retro Guru

hamtaro145

Dirt Disciple

FluffyChicken

m88arx

Retro Guru

Attachments

m88arx

Retro Guru

Similar threads

Latest posts