Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 04-04-08, 02:32 PM   #1
bert37
Senior Member
Thread Starter
 
Join Date: Aug 2005
Bikes:
Posts: 53
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Excessive toe-in on one brakepad

hey all

(sorry, I meant for this to go in the Mechanics forum...)

just bought a new pair of Shimano Deore brake pads, for a Linear Pull caliper setup. As a novice, I carefully followed the Park Tools 'Big Blue Book' instructions to install the new pads. The right pad is set very nicely. However, the left pad is very excessively "toed-in" -- i.e., the front of the pad is rubbing the rim, while the back is not even close. The pad is at probably a ~15-20 degree angle away from the rim.
What might I be doing wrong here? I've re-adjusted the nuts/washers on that side, several times, but the pad ends up in the same (mis)alignment. Would installing the pad with a shim at the front help? Is it possible that the pad is defective / warped?


thanks much,

Last edited by bert37; 04-04-08 at 02:36 PM. Reason: d'oh: posted in wrong forum
bert37 is offline   Reply With Quote
Old 04-04-08, 02:39 PM   #2
_dhan_
Amateur Hack
 
Join Date: Oct 2005
Location: Austin
Bikes: Marin mtb turned tri turned commuter turned singlespeed, Haro Werks 2.0, Specialized Epic Allez carbon main tube built up for triathlons
Posts: 135
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
try try again!
loosen the nuts/washers on that side even more than you did before and try to adjust the angle of the pad. If you still can't fix the pad angle, then squeeze the brake lever while that pad is loose. That should flatten it out. You can stick a small coin under the appropriate side prior to squeezing to achieve a reasonable toe-in.
_dhan_ is offline   Reply With Quote
Old 04-04-08, 07:12 PM   #3
bert37
Senior Member
Thread Starter
 
Join Date: Aug 2005
Bikes:
Posts: 53
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by _dhan_ View Post
try try again!
heh... good advice. I got it much closer on the sixth (or so) try. still a bit more angled than I'd like (I think), but I'm guessing it'll flatten out some over time..

thanks for the response...
bert37 is offline   Reply With Quote
Old 04-04-08, 07:28 PM   #4
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Bikes: Rans Rockst (Retro rocket) Rans Enduro Sport (Retro racket) Catrike 559, Merin Bear Valley (beater bike).
Posts: 26,543
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 62 Post(s)
Quote:
Originally Posted by bert37 View Post
just bought a new pair of Shimano Deore brake pads, for a Linear Pull caliper setup. As a novice, I carefully followed the Park Tools 'Big Blue Book' instructions to install the new pads. The right pad is set very nicely. However, the left pad is very excessively "toed-in" -- i.e., the front of the pad is rubbing the rim, while the back is not even close. The pad is at probably a ~15-20 degree angle away from the rim.
What might I be doing wrong here? I've re-adjusted the nuts/washers on that side, several times, but the pad ends up in the same (mis)alignment. Would installing the pad with a shim at the front help? Is it possible that the pad is defective / warped?
Hmmm. Sounds akin to the all-to-common saddle angle problem to me.

With saddles the problem is that guys try repeatedly to loosen the clamp bolt and reposition the saddle only to have it resume the exact same angle. The cause is that the bottom part of the saddle clamp is stuck and doesn't move even after the clamp is loosened. The cure is to knock the bottom part of the clamp loose, reposition the saddle and retighten the bolt.

I'm wondering if the same thing has been happening with your brake. The next time that you loosen the bolt, make sure that the spherical washers are knocked loose before you try to reposition the pad. My bet is you'll find one of those washers is stuck.
Retro Grouch is offline   Reply With Quote
Old 04-04-08, 08:29 PM   #5
trekkie820
Senior Member
 
Join Date: Feb 2004
Location: Cleveland, OH
Bikes: 2004 Trek 4600, 1980's Univega Supra Sport, 2006 Lemond Reno
Posts: 2,287
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Anytime you install pads do this: 1) Position the pad where you want it on the rim. Typically, you want a toe in setup. To get this, put a business card on the rear of the brake pad, making sure it is ONLY ON THE REAR part. 2.) Hold the corresponding brake lever as tight as you can and tighten down the nut holding the pad on. Repeat for each pad.
trekkie820 is offline   Reply With Quote
Old 04-04-08, 10:32 PM   #6
christama
Senior Member
 
Join Date: Mar 2008
Bikes:
Posts: 72
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I've been running into this a lot lately. It seems like some of the washers aren't smooth enough for the pads to wiggle on the concave/convex surfaces. A little grease anywhere those washers touch seem to make adjustment much easier.
christama is offline   Reply With Quote
Old 04-05-08, 08:51 PM   #7
skylla
Senior Member
 
Join Date: Aug 2007
Location: Philadelphia, PA
Bikes:
Posts: 109
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
The Park book might already have a similar tip, since the instructions on the Park web site do (they recommend a piece of rubber band), but I just toed my pads with little rings cut from an old tube. Better than a business card or a coin, I think because you just slip them over the end and don't have to hold them in place.

My approach to your problem would be similar to what's been said: loosen up a lot, wiggle everything around a bit (maybe twist the concave/convex washers in different directions so they can't sit exactly the way they were doing before), then hold the pad against the rim, put tension on the cable (I tie something around the lever. there might be a more sensible way), and tighten.
skylla is offline   Reply With Quote
Old 04-06-08, 12:30 PM   #8
onbike 1939
Senior Member
 
onbike 1939's Avatar
 
Join Date: Dec 2004
Location: Fife Scotland
Bikes: Airnimal Chameleon; Ellis Briggs; Moulton TSR27 Moulton Esprit
Posts: 1,990
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 45 Post(s)
Quote:
Originally Posted by christama View Post
I've been running into this a lot lately. It seems like some of the washers aren't smooth enough for the pads to wiggle on the concave/convex surfaces. A little grease anywhere those washers touch seem to make adjustment much easier.
+1 Much easier with the concave/convex surfaces greased.
onbike 1939 is offline   Reply With Quote
Old 04-06-08, 12:53 PM   #9
kenhill3
use your best eye
 
kenhill3's Avatar
 
Join Date: Mar 2006
Location: Olympia, Washington
Bikes: '75 Bertin, '93 Parkpre Team 925, '04 Kona King Kikapu, '05 Bianchi Vigorelli
Posts: 3,058
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Funny, I've rarely had an issue with toe-in on V-brakes. Read: V-brakes by design/function require little toe-in if any at all.
__________________
"I tell you, We are here on earth to fart around, and don't let anybody tell you any different." - Kurt Vonnegut jr.
kenhill3 is offline   Reply With Quote
Old 04-06-08, 01:27 PM   #10
Bill Kapaun
Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Bikes: 86 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.
Posts: 9,202
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
What if you swap the pads to the opposite sides?
Bill Kapaun is offline   Reply With Quote
Old 04-06-08, 02:37 PM   #11
operator
cab horn
 
Join Date: Jun 2004
Location: Toronto
Bikes: 1987 Bianchi Campione
Posts: 28,306
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by kenhill3 View Post
Funny, I've rarely had an issue with toe-in on V-brakes. Read: V-brakes by design/function require little toe-in if any at all.
You've clearly never had to assemble lots of low end bikes with v-brakes. If your statement were true, you'd be saving me a heck of a lot of aggravation.
operator is offline   Reply With Quote
Old 04-06-08, 03:29 PM   #12
kenhill3
use your best eye
 
kenhill3's Avatar
 
Join Date: Mar 2006
Location: Olympia, Washington
Bikes: '75 Bertin, '93 Parkpre Team 925, '04 Kona King Kikapu, '05 Bianchi Vigorelli
Posts: 3,058
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by operator View Post
You've clearly never had to assemble lots of low end bikes with v-brakes. If your statement were true, you'd be saving me a heck of a lot of aggravation.
You are right about that! I'm not an assembler of 'lots of low end bikes with V-brakes". My experience only includes higher-end with XT or XTR. Sorry.
__________________
"I tell you, We are here on earth to fart around, and don't let anybody tell you any different." - Kurt Vonnegut jr.
kenhill3 is offline   Reply With Quote
Old 04-06-08, 05:00 PM   #13
operator
cab horn
 
Join Date: Jun 2004
Location: Toronto
Bikes: 1987 Bianchi Campione
Posts: 28,306
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by kenhill3 View Post
You are right about that! I'm not an assembler of 'lots of low end bikes with V-brakes". My experience only includes higher-end with XT or XTR. Sorry.
You lucky *******. The low end v-brakes either have a lot of play in them (causing squealing), the brake pads are shyte (causing squealing) or the rims are shyte (causing squealing).

Argh.
operator is offline   Reply With Quote
Old 04-06-08, 05:06 PM   #14
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Bikes: Rans Rockst (Retro rocket) Rans Enduro Sport (Retro racket) Catrike 559, Merin Bear Valley (beater bike).
Posts: 26,543
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 62 Post(s)
Quote:
Originally Posted by operator View Post
You lucky *******. The low end v-brakes either have a lot of play in them (causing squealing), the brake pads are shyte (causing squealing) or the rims are shyte (causing squealing).

Argh.
Worst of all the lower end Shimano V-brake offerings are hugely better and can't cost more than a few pennies more. ProMax sucks! Why do those things even exist?
Retro Grouch is offline   Reply With Quote
Old 04-06-08, 05:25 PM   #15
operator
cab horn
 
Join Date: Jun 2004
Location: Toronto
Bikes: 1987 Bianchi Campione
Posts: 28,306
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Retro Grouch View Post
Worst of all the lower end Shimano V-brake offerings are hugely better and can't cost more than a few pennies more. ProMax sucks! Why do those things even exist?
Oh trust me, these are lower end than promax.
operator is offline   Reply With Quote
Old 04-06-08, 05:41 PM   #16
kenhill3
use your best eye
 
kenhill3's Avatar
 
Join Date: Mar 2006
Location: Olympia, Washington
Bikes: '75 Bertin, '93 Parkpre Team 925, '04 Kona King Kikapu, '05 Bianchi Vigorelli
Posts: 3,058
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by operator View Post
Oh trust me, these are lower end than promax.
How do you guys rate the Tektro line?

I recently installed some Tektro's on my GF's commuter, particular model made with slightly longer arms to clear fenders, what a good idea. The Tektros seem to perform just fine, look similar to low-end Shimano.
__________________
"I tell you, We are here on earth to fart around, and don't let anybody tell you any different." - Kurt Vonnegut jr.
kenhill3 is offline   Reply With Quote
Old 04-06-08, 06:36 PM   #17
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Bikes: Rans Rockst (Retro rocket) Rans Enduro Sport (Retro racket) Catrike 559, Merin Bear Valley (beater bike).
Posts: 26,543
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 62 Post(s)
[QUOTE=kenhill3;6472402]How do you guys rate the Tektro line?[QUOTE]

I've gotten inconsistant results with Tektro linear pull brakes. Back in '97 or '98 I had a real good opinion of them but it gradually diminished over the years. I suspect their quality control is iffy and it depends a lot on the individual set that you get.

I don't have enough experience with Tektro caliper brakes to have formed an opinion but I've heard a lot of good reviews about them. My issue with them is they're roughly the same price as Shimano so why take the chance?
Retro Grouch is offline   Reply With Quote
Old 04-07-08, 10:20 PM   #18
bert37
Senior Member
Thread Starter
 
Join Date: Aug 2005
Bikes:
Posts: 53
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by onbike 1939 View Post
+1 Much easier with the concave/convex surfaces greased.
Thanks again for all the responses. I do think the grease helped on the final (successful) try, as did just messing around more with the nuts & washers.

Btw, I couldn't swap sides because the pads are specifically-marked for L & R, and designed off-center (i.e., more pad behind the bolts than in front).


cheers,
bert37 is offline   Reply With Quote
Old 04-07-08, 10:42 PM   #19
operator
cab horn
 
Join Date: Jun 2004
Location: Toronto
Bikes: 1987 Bianchi Campione
Posts: 28,306
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by kenhill3 View Post
How do you guys rate the Tektro line?

I recently installed some Tektro's on my GF's commuter, particular model made with slightly longer arms to clear fenders, what a good idea. The Tektros seem to perform just fine, look similar to low-end Shimano.
Their v-brakes are sort of not so great. Their dual pivot short, medium, long reach calipers are excellent value - good quality, good price
operator is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 01:32 AM.