ziggycj

One side of my brakes kept touching the rim. I tried adjusting the tension screws on both sides but nothing moved. I loosened the brake cable but this just meant theright side became lose sonow barely touches the rim. I tried adjusting the caliper bolt near the screw but heard a clang.

When pulling the brakes only the right side moves in and out. The Left side is always tight in. I removed the brake pad and the left side snapped further in towards the rim.


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BTinNYC 

Ziggy,
Have you removed the calipers from the frame and checked the return spring? I think the weak side spring might have an issue.
Park Tool's vid is good and covers a lot of set-up and adjustment;

FBinNY 

Contrary to mythology, springs do not weaken over time with normal use.

IME the only way a spring would weaken or deform is if forced beyond it's working limit by, for example, if the brake arm being forced far beyond normal with the wheel off. This could be reversed by disconnecting the cable and pulling the arm back comparably.

But before considering the springs, look for more likely causes, like friction between arm and post, or the cable tugging on the caliper arm.

Afterthought----

If this has been a problem from the beginning, and not something new, it MIGHT be that the mount has multiple spring holes, and you mismatched the two sides.

Last thought. While springs don't weaken, there's always the possibility of one failing completely, ie. snapping. That would be obvious on disassembly.

soyabean

Remove the bolts AND remove the arms.

You will see that all lube have gone away or caked up.

Do not re-lube. Clean off all that old hardened crap first.

I don't grease these. I prefer high pressure synthetic oil that will never "dry" out.

Upon reinstall you will find how well they work with almost no or minimal tension (screws very out).

oldbobcat

If cleaning, lubrication, and working the tension screws doesn't cut it, I'm not too proud to unhook the long end of the spring from the weak-side caliper and give it an outward tweak. Of course, sometimes the coil end is anchored in a plastic housing, and sometimes the housing breaks. Then it's time for replacement.

Andrew R Stewart 

When the centering issue is solved (pivot grime, spring imbalance, cable/casing stuff) be sure to better position the pads against the rim. The image posted shows nearly half the LH pad off the rim's surface. Andy

Davet

In addition to the above, it appears that the OP is using compressionless brake housing which is pushing the V-brakes to the drive side. Those housings are too stiff to allow any of the necessary flexibility of the system, which would allow the brake tension screws to bring the brake arms into a central, relaxed position.

ziggycj

Hi all,

Thanks for your advice and tips. I've managed to fix the spring issue (the clang was it disconnecting, I took the arm off and refit the spring). But now back to the original reason why I was messing with the spring in the first place, the brake is still touching the rim every rotation.

I don't think it's a break issue those, pretty sure it's a wheel truing issue. I'm not sure how to add video, but the wheel touches even when the brakes are very loose.

ziggycj

Do you have any recommendations for an oil? I only have grease or lubes (and WD-40/GT-85)

Andrew R Stewart 

Just about any lube is better then none. Don't get too worried which you use here. Andy

JoeTBM 

When you remove the arms, look to see if there is any corrosion on the pivot ring (brass mostly) and clean using a gun barrel wire brush (I find 9mm .38 are best).

Clean the brake bosses with steel wool

We lube with Mobile 1 synthetic.