Mountain Bike Reviews Forum banner
1 - 20 of 26 Posts

·
Old school BMXer
Joined
·
2,695 Posts
Discussion Starter · #1 ·
Contrary to advice listed in another thread where Intense recommends using a Shimano FD-M960 or equivalent, there are better fitting derailleurs.

The 960 (XTR) or 760 (XT) will work, but for good fitment you have to grind the swing arm to clear the limit screws (there is a little clearance at rest, but they hit the swing arm on compression). Also, the cage hits the swing arm just above the indention, requiring that area to be ground. Or, you can run an excessive amount of spacers in the bottom bracket. For all of these reasons, the above mentioned derailleurs are not a good choice.

If you want a front derailleur that fits properly, use the Shimano FD-M750 (older XT). There is about 3/4" of clearance between the limit screws and the swing arm, and the cage fits nicely in the indention. The FD-M950 (XTR) derailleur doesn't fit very well since the parallel-swing cage takes up valuable space, making it not fit very well.

I am also using the latest XT cranks set up as a double (with a 36t chainring and a bashguard). I am not running any additional spacers in the bottom bracket than what Shimano recommends for a 73mm shell width. With the 750 derailleur, I'm sure I can run a triple up front. When I get a chance, I'll try it, and post back.

I don't know about Deore or LX derailleurs, but I bet the older versions fit better.

In short, the VPX was apparently designed to use an older, now obsolete front derailleur. Buy 'em while you can find them!

Lee
 

·
rain rain go away...
Joined
·
1,195 Posts
i totally agree w/. buying the older type. intense doesn't seem to agree w/ this... but we know. :D

i personally would not let any grinding device to touch my frame. i ground the FD instead and i even trimmed the screw that's holding the actual arm together. i will post a shot of it shortly. the Deore are still using the older style so u can run those.

the red line represents the shimano widelink design... hits the rear triangle.





 

·
Bike Hoor
Joined
·
675 Posts
I am using an 05 LX.. the screws are accessible, and it adjusts well. Only real issue is that with the suspension fully extended on a race stand, the chain rubs the lower part of the cage in the first chainring. I can't get the derailleur any lower than it is. The cage does seem to fit nicely into the cutout, although (again, fully extended), there is about a business card width sized space between the case and the swingarm. Once sitting on the bike, all is good. Since the derailleur never touches the swingarm with the shock fully extended, it (theoretically) should never hit the swingarm when riding, even when in the air.

Is that also something you notice on the older XT?
 

·
rain rain go away...
Joined
·
1,195 Posts
IB,

that's why i did some creative grinding on my bracket to lower the FD..... so to provide more clearance to the chain when on the smaller ring.

can u provide us w/ a shot of your FD like i did on mine? u said u have a 2005 LX... i have a 2005 Hone which is suppose to be IDENTICAL to your LX. but no way for me to mount it. red line on my picture shows how wide this WIDELINK design from shimano is.









 

·
Old school BMXer
Joined
·
2,695 Posts
Discussion Starter · #7 ·
Innocent Bystander said:
I am using an 05 LX.. the screws are accessible, and it adjusts well. Only real issue is that with the suspension fully extended on a race stand, the chain rubs the lower part of the cage in the first chainring. I can't get the derailleur any lower than it is. The cage does seem to fit nicely into the cutout, although (again, fully extended), there is about a business card width sized space between the case and the swingarm. Once sitting on the bike, all is good. Since the derailleur never touches the swingarm with the shock fully extended, it (theoretically) should never hit the swingarm when riding, even when in the air.

Is that also something you notice on the older XT?
How close are the screws? Even with the 960/760 the screws are accessible, but they are really close to hitting the rear swing arm. Once you compare the 960/760 with the 750, it is quite obvious what the differences are. I took some photos with both of them on my VPX, but they didn't come out well. Could you please post pics of your LX derailleur?

Yes, when the bike is in the stand the chain does rub on the bottom of the cage when it is in granny gear (I don't remember the gear range in the rear that allows this to occur). This is normal. Not only do I have this on my VPX, it's also that way on the 5.5. BTW, this may also be a function of it being a shorter cage derailleur (I have a 750 on my 5.5 also). When I had a 760 FD on the VPX, with the shock spring removed, the rear swing arm would actually hit the cage of the derailleur. I think the 750 cage (and maybe the LX cage) is shorter than the 960/760 cage (I honestly haven't checked with the 750 to the same degree, but it seems further away).
 

·
rain rain go away...
Joined
·
1,195 Posts
short cage rear D should not have anything to do w/ the chain hitting the lower part of the FD. it's how small the small front ring is and how low... or high in our case, we have mounted the FD.

post pictures, worth a thousand words?
 

·
Old school BMXer
Joined
·
2,695 Posts
Discussion Starter · #10 ·
peachy-B said:
short cage rear D should not have anything to do w/ the chain hitting the lower part of the FD. it's how small the small front ring is and how low... or high in our case, we have mounted the FD.

post pictures, worth a thousand words?
I'm not talking about the rear derailleur - I am talking about the front. The 760 hung down lower to the swing arm more than the 750 does (hence I called it a long cage). However, my means of measuring aren't accurate. By the way, you can mount the 750 FD lower than the 760, if you wanted to.
 

·
Bike Hoor
Joined
·
675 Posts
One thing we all seem to be overlooking is bottom bracket spindle length and rear drop out spacing. I am running 135mm spacing with a 118mm bottom bracket spindle. You guys?

Very innovative approach Peachy. I like it. I wonder if the small frame poses more problems than the medium frame.

I will post pix in a few minutes of my front der mounting. I spent 30 minutes trying to tune out the chain drag on the bottom of the cage before thinking about sag. Duh. Did the same thing on the first 575 I built before I realized that very thing. Why I didn't remember that tidbit when building the Uzzi I have no freakin' idea.
 

·
Bike Hoor
Joined
·
675 Posts
Here are the pix...

Excuse the color differences, I had to doctor the photos to make them look decent. Not enough light to get great pix. Also excuse the mud, just got back from a ride. :D
 

Attachments

·
rain rain go away...
Joined
·
1,195 Posts
IB,

i dnt know what my spindle length is. just bought the diabolus crank and that's it. :D i seem to have plenty of engagement on the spindle and spider.

i'm running 135mm in the back.

looks like we have a similar style "older" front D. i have added more images on my posting above.
 

·
Old school BMXer
Joined
·
2,695 Posts
Discussion Starter · #14 ·
That LX derailleur is the same setup as the 750 (XT) derailleur that I am suggesting to use.

As I mentioned, I am using the standard 760 XT cranks (built in BB spindle), and I am using the 135 axle spacing. Comparing spindle length is all but meaningless when refering to different types of crank designs. In all reality, none of this changes the adjusting screws hitting the frame, using a long spindle only allows you to get the cage further away from the vertical part of the swing arm where the indention is. Using an excessively long spindle is only a band-aid for another issue (such as trying to use a 960/760 derailleur).
 

·
urbantrailridingroadie
Joined
·
502 Posts
still a little confused

does the 760 work on the Med?

It sounds like some are saying yes, while are disagreeing. The reason I ask is IB suggested to use the LX 580, but the shop where I'm having the bike built says they use the XT M760 (28.6-34.9) with no problems.

Can someone confirm or deny this for me.

They are starting my build next week and I would like to have all the bugs worked out.

Thanks for help
tep
 

·
rain rain go away...
Joined
·
1,195 Posts
tep,

my answer to the 760 question is NO. that's my guess from what i have experience on the Hone's Wide Link Design which is also similar to the LX and the XT. This is ON MY SMALL FRAME. i can't speak for the other sizes since i dnt have access to them.

as for big squishy, why would u wanna get a special FD... u can use a normal one. just modify it a bit. :D works super fine for me.

shots of the Hone that did NOT fit for me.



 

·
Old school BMXer
Joined
·
2,695 Posts
Discussion Starter · #19 ·
tep,
My VPX is a medium.

Yes, you can MAKE the 760 work by doing a bunch of goofy stuff like spacing the drive side crank out a bunch or by grinding a ton of material off the swingarm. Even still, there is another part of the swing are that may need a slight bit of grinding. So it's not impossible to make the 760 work, by why do a bunch of hoky stuff? Just get a 750 or an LX or Deore derailleur and do it right. Your shop that says the 760 works fine has probably never done one, or has never used one of the above mentioned derailleurs to see how nice it can be done.

I have no idea about the SRAM derailleurs, but there is no need for a "special" derailleur.
 

·
rain rain go away...
Joined
·
1,195 Posts
i nearly swallowed my heart when you said "by grinding a ton of material off the swingarm". augh! no way in hell i would something like that. if u get the LX (same as hone posted above)... get last year's.

there are tons of info here so that u dnt have to touch your frame w/ your dremel.
 
1 - 20 of 26 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top