Bicycle Mechanics - V brakes wont stay centered

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View Full Version : V brakes wont stay centered


phantomcow2
05-07-05, 05:26 PM
I notice lately that my V brakes will not stay centered. I adjust it in the morning, by the afternoon they are way off. So i carry a 3mm allen wrench in my pocket now. I have avid single digit brakes, is there anything about this that I can do? Or is this just the nature of V's. I dont remember them being a problem when i got them and not really until the past few weeks.


khuon
05-07-05, 05:29 PM
If the adjustment screws won't work, you might want to try bending the springs.

cavernmech
05-07-05, 05:49 PM
If the adjust screws keep spinning back out...a tiny drop of blue loctite on the threads to keep em in place.


jeff williams
05-07-05, 05:57 PM
I don't adjust them by screwing in the tension screw.
If adjusting, I flip the spring\bars off, tighten the screws, then put the bars on and only loosen the screws to adjust.
If it gets too 'adjusted' I start over.

Bikewer
05-07-05, 06:24 PM
I don't know why it would make a difference, but some of our bikes are set up with Avids, and they are a pain to keep centered. The Shimanos (mostly LX) on the other bikes never seem to have any problems.

steveknight
05-07-05, 06:41 PM
my avid single digit 7's did that every time I touched them. paul component v brakes are a breath of fresh air so much easier to keep adjsuted. far more powerful too.

Rev.Chuck
05-07-05, 07:42 PM
Usually this happens because there ie a little corrosion or burring in the bushing that the arm pivots on. These brakes do not turn on the stud it is just a mount point.
The simple fix is to buy some Deore level Shimano linear pulls, they are cheap and stay adjusted real well. The fix it guy aproach is to take the arms off disassemble the pivot and clean both the pivot and bore with some fine sand paper. Grease it and put it back together. When you reinstall the arm use loctite, just a little, on the threads and do not crank it down, as this can flare the bushing and make the brake sticky.

phantomcow2
05-07-05, 07:44 PM
Usually this happens because there ie a little corrosion or burring in the bushing that the arm pivots on. These brakes do not turn on the stud it is just a mount point.
The simple fix is to buy some Deore level Shimano linear pulls, they are cheap and stay adjusted real well. The fix it guy aproach is to take the arms off disassemble the pivot and clean both the pivot and bore with some fine sand paper. Grease it and put it back together. When you reinstall the arm use loctite, just a little, on the threads and do not crank it down, as this can flare the bushing and make the brake sticky.
well it looks like im going to be taking apart that brake. Its odd though, I bought these things in January i think might have been late december. would there be that much corrosion in just 4 months?

Rev.Chuck
05-07-05, 08:14 PM
It does not take much. It can also be from tightening down on the bolt to hard. They work better if the bushing/bore interface is a little sloppy and the Avids are pretty close.

phantomcow2
05-07-05, 08:21 PM
Do you mean the bolts that hold the arm to the stud?

Rev.Chuck
05-07-05, 08:55 PM
Yeah, on these brakes the arm does not pivot on the stud, it pivots on the bushing you can see sticking just above the body of the arm. When you crank the retaining bolt, the one holding the arm on the stud, it can flare the bushing and you will never get a decent adjustment. While it is not a good idea to ride the bike around with these bolts loose, you might try loosening the bolts and see if it lets the arms stay adjusted better. Then take it apart and clean up the bushings with some emery cloth.

phantomcow2
05-07-05, 08:58 PM
Yeah, on these brakes the arm does not pivot on the stud, it pivots on the bushing you can see sticking just above the body of the arm. When you crank the retaining bolt, the one holding the arm on the stud, it can flare the bushing and you will never get a decent adjustment. While it is not a good idea to ride the bike around with these bolts loose, you might try loosening the bolts and see if it lets the arms stay adjusted better. Then take it apart and clean up the bushings with some emery cloth.
ugh, Is it just the single digit 5 brakes that i have? Or all avid brakes that do this, or all V brakes.

Rev.Chuck
05-07-05, 09:05 PM
It can happen on a lot of them, surprisingly the cheap Shimanos have litlle trouble with this. The ones I use as replacements are not even Deore, they retail for $12 and work very well.

Dannihilator
05-07-05, 09:23 PM
That's what I love about disc brakes.

phantomcow2
05-07-05, 09:40 PM
It can happen on a lot of them, surprisingly the cheap Shimanos have litlle trouble with this. The ones I use as replacements are not even Deore, they retail for $12 and work very well.
Is there any way to tell if they will have this problem when buying?

Rev.Chuck
05-07-05, 09:57 PM
Not that I know of, other than looking around at reviews.

steveknight
05-07-05, 10:06 PM
mine did it on my new bike. I cleaned the studs and regreased them the same thing. if you touched the brakes one side would not move so you had to use the tension screw then after a ride or two they went back to where they were and you had to undo the tension screw on the side you just did it on.always the same even if I took the brakes off and cleaned the sleeve and evertyhing. the bolts were nto tight and held in place with locktite.
the cheapie shimano's worked fine. they took a lot less spring tension too.
same with the paul's far less spring tnesion on them. someone else told me their sd7'd did the exact same thing.

neil0502
05-07-05, 10:07 PM
That's what I love about disc brakes.

That milk guy is satanic and freaked out my neighbor's dog. I'm calling a priest. You're in *big* trouble :)

Karldar
05-07-05, 10:09 PM
I notice lately that my V brakes will not stay centered. I adjust it in the morning, by the afternoon they are way off. So i carry a 3mm allen wrench in my pocket now. I have avid single digit brakes, is there anything about this that I can do? Or is this just the nature of V's. I dont remember them being a problem when i got them and not really until the past few weeks.

Just so I'm clear, are you talking about the brake pads being equidistant from the rim or being centered on the rim itself(when they contact it)? I've got XTR V's on both my bikes and I've never even touched the 3mm bolts. I just pop the spring and bend it out a little to get the pads where I want 'em. Maybe my brain's just having trouble processing your problem. Had a long ride today and got more sun than I should have.

khuon
05-07-05, 10:13 PM
I guess I must be the oddball here. I've never had any of these problems with my Avid ArchRival 50s.

Rev.Chuck
05-07-05, 10:26 PM
The arch rivals have the cross bridge, right? they have a heavy duty pivot point, where that bridge is attached and don't have this problem. You spent the extra $$ and saved your self some trouble.

P.S. My older MTB has the xt's with the, much complained about, squealy problem but they never gave me a moments trouble. New bike has avid disks, quiet, no adjustment problems.

phantomcow2
05-08-05, 06:05 AM
Just so I'm clear, are you talking about the brake pads being equidistant from the rim or being centered on the rim itself(when they contact it)? I've got XTR V's on both my bikes and I've never even touched the 3mm bolts. I just pop the spring and bend it out a little to get the pads where I want 'em. Maybe my brain's just having trouble processing your problem. Had a long ride today and got more sun than I should have.
They contact at different times and are not equidistant. Yesterday while riding my brake pads on the right side were actually scraping the rim! I look at the reviews for the SD5 and they are fantastic :(. But yesterday i cleaned off the stud and all the internals i could see so i will see how it works today. If i somehow aquire a lump sum of $ i will look at those Paul motolites

Raiyn
05-08-05, 10:43 PM
I guess I must be the oddball here. I've never had any of these problems with my Avid ArchRival 50s.
Nor I with my Arch 40's.

seely
05-08-05, 11:02 PM
My SD5's do it, but my plain ol' SD3's didn't. I'm not sure what the issue is. It comes and goes on the SD5's very randomly.