Bicycle Mechanics - Adjusting Linear Pull Brakes

I am having a struggle adjusting my linear pull brakes. I know this should be simple but i am a newbie. My problem is that regardless of what I do, I can't get the left (side opposite the deraillers) to pull away from the rim. It just rests on the rim. This article (http://www.parktool.com/repair_help/howfix_linearbrakes.shtml) should help me but doesn't seem to.

Try adjusting the tiny set screws on each brake arm. They control the return spring tension. That is your problem.
Also, if you installed these brakes yourself, make sure you allowed enough cable housing slack to allow free movement of the arm.

George

Try adjusting the tiny set screws on each brake arm. They control the return spring tension. That is your problem.
Also, if you installed these brakes yourself, make sure you allowed enough cable housing slack to allow free movement of the arm.

George


I didn't install the brakes. I was just trying to tighten them up. The only way I could get the brakes stiffer and the slack out of the cable was to unscrew the thumbscrew all of the way.

WHen I try and take up the slack at the fixing screw it pushes the left arm against the rim like i previously mentioned. I would like to be able to have the thumbscrew all of the way in so I can have some adjustment. I just don't know how to get it that way.

Right now i have the brakes working fine but there is a lot of slack in the cable. I can take it up if i adjust the thumbscrew but it will then be all of the way out.

To remove the cable slack you're talking about, loosen the cable end on the brake arm, pull a bit more cable, then tighten.
As I said before, to balance arm tension......adjust the tiny screws/allen bolts located near the base of each arm.

George

It also seems like my right caliper sticks out farther than it should. However when i try and correct this by lessening the amount of cable between the fixing screw and the other caliper it makes it so the right caliper is smashed up against the rim and I can't adjust for it.

My other bike seems to have less of a distance between calipers as seen in the photos.

To remove the cable slack you're talking about, loosen the cable end on the brake arm, pull a bit more cable, then tighten.
As I said before, to balance arm tension......adjust the tiny screws/allen bolts located near the base of each arm.

George

Maybe i am not actually pulling any cable. I don't have a 3rd hand tool. When I pull the tops of the calipers closer, the left pad continues to rub against the rim. I can adjust the screw on the little caliper all the way but it still happens. I'll keep playin.

Maybe i am not actually pulling any cable. I don't have a 3rd hand tool.

You don't need a 3rd hand tool. Use your fingers.

George

You don't need a 3rd hand tool. Use your fingers.

George

And maybe a brain. :D Thanks fixer. I think i got it now. I took the slack out of the cable and messed with it til i got it. Like I said, i am new at screwing with bikes so appreciate the help.

I don't think bikes are beyond my ability (spent last 12 years working on copy machines and fax machines) but I am a little mentally challenged. :cry:

If the little adjusting screw just above the arm pivot is on the RH side of the bike, you unscrew it to move the RH pad closer to the rim and the LH pad further from the rim.

If the little adjusting screw just above the arm pivot is on the RH side of the bike, you unscrew it to move the RH pad closer to the rim and the LH pad further from the rim.

The attachment below (if it works) shows the little bolts AndrewP is talking about.

Normally, you should either unscrew the bolt on the left side, or screw the bolt on the right side. Just make sure you don't turn them with a tight grip as they are tiny bolts. Depending on the brake, you either need a small Phillips screwdriver or a 2.5-3 mm Allen wrench. Once things look OK, apply the brakes 2-3 times and make sure things are still centred. It's a bit of trial and error, but if things work correctly, you will definitely see an improvement when you turn one or both bolts.
(BTW, some brakes have only 1 bolt on one side).


There are however a few other things you should check too.

1st check (even before the above adjustment):
Check to see that the wheel is straight. If the wheel isn't, there will be a point where the brake pad will rub. If you spin the wheel and the right pad rubs at some points, then the left one at other points, you first need to true the wheel. I doubt this would be your problem, but that's the first check anyway.

2nd check (also before the above adjustment):
Try to wiggle the brake arms left and right to make sure that both arms move freely. If they don't move freely, then you should first remove the brake arms (release cable tension first by removing the noodle from the arm) by unscrewing the big pivot bolt at the base, then adding grease on the pivots. I have do do this once per year on my commuter bike which is used year round, including today at -30 C.

3rd check:
Make sure nothing prevents free movement of both brake arms. For instance, on my touring bike, the panniers may touch one of the brake arms or the brake cable, and that would pull the brake to one side. From what I've seen, it's especially a problem with large frame sizes (I have 25" frame bikes).

Unhook the cable hanger (quick release). Push each lever by hand to the rim to test the return spring. Is one side completely dead? If so, the spring may have come disengaged, or it may be broken. If the pad is mal-adjusted to the rim, it can cause the pad to jam or stick, preventing it from pulling away easily.