Brakes.

Strickland

First post on the MTB section, so howdy!

I changed the brakes pads on my MTB the other day. For a couple of days, everything was great. But now, on the rear wheel, one brake pad is constantly in contact with the wheel rim, so much so that when Im just pushing the bike along the wheel will just stop moving altogether because of the friction caused. Im not sure if it was like this with the old pads, but if it was I never noticed it.

I've tried adjusting and tinkering as much as I know I can to try and sort it, but to no avail. Anyone know how to sort this, or what it could be?

The Northern Monkey

Hello there...

1st off, what brakes are they?

Strickland

bigbenj_08 wrote:

Hello there...

1st off, what brakes are they?

As in, what type, or brake model?

If type, they're v-brakes. If model, they're just what came with the bike. I forget to mention this bike is nothing special. An okay-ish Giant model. If it was a school student, it would be the one that does just enough to pass, but is never bothered about being top of the class.

P.S You may have to be a bit slow with me. I've only just started taking this cycling lark seriously, and am still learning the basics.

chedabob

Are you sure the wheel isn't bent?

If it's not, are the brakes threaded or threadless? If they're threadless (you lock them in place with a nut on the actual brake arm), just unscrew the problematic one and line it up again. If threaded, try rearranging the washers if there are any.

kaytronika

I haven't dabbled with my V's in a while but with cantilevers some frames have three seperate holes for the spring in the body of the brake to go in to to make for more or less tension on the brakes, if you missmatch, the brakes lie to one side more than the other.

Also there are screws on some sets of brakes just above and to the side of where they are mounted in to the frame bosses... Adjusting those allows you to micro adjust the tension in the springs and should allow you to move the incorrectly place brake off the rim.

Strickland

kaytronika wrote:

I haven't dabbled with my V's in a while but with cantilevers some frames have three seperate holes for the spring in the body of the brake to go in to to make for more or less tension on the brakes, if you missmatch, the brakes lie to one side more than the other.

Also there are screws on some sets of brakes just above and to the side of where they are mounted in to the frame bosses... Adjusting those allows you to micro adjust the tension in the springs and should allow you to move the incorrectly place brake off the rim.

I thought this could be it. Went to check this, and the frame does have the three small holes, but the brakes don't have the small bit of metal that fits into these holes.

Chedabob, I don't think the wheel is bent. I am looking to start upgrading bits and pieces on the bike anyway (or maybe going for a new bike altogether) now I am starting to take it all a bit more seriously. Brakes and a decent pair of wheels were on the list. Maybe worth just upgrading these first?

supersonic

There should be two small screws, one on each brake arm that adjust the tension of the spring. WIth the pad that is touching, screw the screw in a bit.

Also ensure pads are lined up and is not undercutting the rim.

Oxygen Thief

This was the case with mine after buying it form Halfords

I tried those screws but they wouldn't move the spring out far enough so had to resort to taking the arm off and putting the spring into one of the other holes. It was really easy.

If, like you say that brakes doesn't have the metal bit to side in one of the holes then that's a bit strange aint it? That's the bit that gives the spring tension in pushing out form contacting the wheel.

Strickland

supersonic wrote:

There should be two small screws, one on each brake arm that adjust the tension of the spring. WIth the pad that is touching, screw the screw in a bit.

Also ensure pads are lined up and is not undercutting the rim.

I've also checked for this. These too are missing from the brakes on my bike. Looking at the bike, none of the obvious routes that could cause problems are adjustable on these brakes.

Just looking at the brake again, one arm (the one that's the problem) does lean over towards the wheel, with the other arm leaning away from the wheel. The front brakes are fine and have had no problems since changing the pads, just the rear ones. :?

kaytronika

Definately sounds like a discrepency in the spring tension somewhere.

Did you remove the brakes to fit the pads?

chedabob

Have you touched the bolt that holds the arm onto the frame? I overtightened mine and it stopped one of the arms from returning properly

kaytronika

Also, a silly suggestion... But check the routing of the cable at the rear... If it's hooked round something it could be pulling the brakes to one side.

I always suggest silly suggestions because that's where I usually go wrong.
Spent 15 minutes trying to screw a cleat on to an SPD shoe upside down the other week.

spincycle

Another suggestion - check that your wheel is seated correctly in the dropouts and the rim is centered between the seat/chain stays.

ride_whenever

spincycle wrote:

Another suggestion - check that your wheel is seated correctly in the dropouts and the rim is centered between the seat/chain stays.

This is what i'd check first. New pads shouldn't massively alter the required spring arm tension, putting the wheel in wonky (which is far easier than one might think) will!

cooldad

Picture always helps - probably something quite simple, but hard to express.

As others have pointed out, they should have little wiry sticky out bits to tension the brakes, and adjuster screws, can't see how they would work without.




.

Strickland

cooldad wrote:

Picture always helps - probably something quite simple, but hard to express.

As others have pointed out, they should have little wiry sticky out bits to tension the brakes, and adjuster screws, can't see how they would work without.




.

Think I know what you're talking about now. I'll have another tinker in the morning, and if I have no luck, will try and get some pics up.