Mountain Bike Reviews Forum banner
1 - 10 of 10 Posts

·
Registered
Joined
·
13 Posts
Discussion Starter · #1 ·
Hi all. I've recently encountered serious rubbing issues with my front derailleur (courtesy of my own stupidity -- I tossed it into the backseat and I believe I un-adjusted or bent the derailleur). I was thinking of maybe just upgrading it, since I can't get it to quit rubbing on the chain, but now I've encountered a new issue. Is this a top swing or bottom swing? The cable travels down and attaches, but the pivot point is above this. Here's a ginormous pic:



(I know it's grimy. I've got a very wet lube on it, since I typically ride paths or hard dirt/gravel-covered areas.)
 

·
Registered
Joined
·
332 Posts
it looks like you pushed the derailleur up higher on the seat tube, based on your dirt patterns. get a shop to check it out, there's probably nothing wrong.
 

·
Dirt Deviant
Joined
·
3,694 Posts
Judging from the picture, it looks like the derailluer was shifted up on the seat tube. You can tell from the dirt ring that it moved up about 5mm. That puts it around 7mm from the chainring, which will make for crappy shifting.
Based on that, it is probably out of alignment as well.
Shift the front down to the small ring, loosen the clamp bolt, slide it back down to the dirt ring, align the cage with the sprockets, and tighten the clamp bolt. You should see an instant improvement.
If you can't get it right, take it to the shop.
It looks like a top swing, top pull.
Or as SRAM would call it, a low clamp top pull.
Most front derailluers these days are dual pull, btw, depending on how you route the cable.
 

·
Class Clown
Joined
·
3,443 Posts
I would say if you have some free time try it yourself. There's a parktool writeup on front derailleur adjustments that can help. Get your back wheel off the ground and do some fiddling. It can be a bit frustrating if you've never adjusted it before but you'll figure it out. I would hate to have to run to the lbs because my FD is out of wack, especially if it took a hit far from home.
 

·
Registered
Joined
·
13 Posts
Discussion Starter · #6 ·
Thanks all... yes, I did push it up a bit I guess. I've now tinkered with that screw and it seemed a bit looser than it ought to be. I don't know if it happened from being put into the car or from me trying to get it into a place where it wasn't rubbing the chain.

Taking it to a LBS is my last resort; they're not really affordable here. The last time I mucked up my derailleur, it cost 30€ to remedy it with a "tune up". For that price, I could simply add another $25 and get a new and better derailleur.

'Course, I'd probably have to take it back in when I can't figure how to adjust it properly. :D But the good thing is this: I've recently gotten into my road bike, so my mtb isn't my main form of entertainment anymore. I do enjoy working on the bikes and learning about them... so I think that if I can get a new part or two, this will be a great experience.
 

·
Suffers From Binge Biking
Joined
·
412 Posts
Any derailer listed as low clamp/ top swing and top pull/ dual pull will work for you. Depending on how low the the water bottle cage bolts are on the seat tube (if you even have them), you may be able to get away with changing to a high clamp/ bottom swing derailer. However, buying a new derailer will not help you to avoid the problem you have, which is a derailer out of adjustment. Learning how to work on you own bike is very rewarding and can be relaxing if you have a few hours to just sit down a play with your bike :D Take you time and find some instructions to follow. This site should help you out:
http://parktool.com/repair/readhowto.asp?id=75
Note that under the "front derailleur height" section, they recommend 1-2 mm of spacing. This usually works on road bikes, but when I tried setting this distance on my mtn bike, shifting sucked. 5mm usually work for me. Like others said though, note where the dirt line is under the derailer and set it back at this height. You may also have to rotate it around the seat tube if the chain is rubbing.
 

·
Registered
Joined
·
230 Posts
There are lots of different sites on the web that explain how to adjust it. Took me a lot of reading and several attempts before I was able to adjust mine. Seemed like my limit screws weren't working right. Almost broke down and took it to the shop, but kept messing with it till I figured it out. Check youtube for videos on derailluer adjustment too.
 

·
A mean teen...
Joined
·
331 Posts
Kelly Mo said:
(I know it's grimy. I've got a very wet lube on it, since I typically ride paths or hard dirt/gravel-covered areas.)
Are these areas that you ride in mainly dry? If so then it's unecessary to have a thick wet lube on the chain, as that'll attract all the gravel and dirt onto the chain: equalling a grindy paste.
 

·
Registered
Joined
·
13 Posts
Discussion Starter · #10 ·
If so then it's unecessary to have a thick wet lube on the chain
Yeah actually, it's normally wet (very rarely can I ride anywhere without hitting puddles). I actually just put this lube on, right before I really quit riding. I do intend to put something a little drier on though... which now that I think abuot it, would probably make the whole derailleur thing easier.

Seemed like my limit screws weren't working right.
Yeah, mine either. Something's really out of whack... they're not even touching the little lever that I assume they adjust.

I'll be taking a look at the link posted, and I hadn't even though of youtube. Thanks again everyone!
 
1 - 10 of 10 Posts
Top