donheff

Still engaged in my bike maintenance 101 learning experience. I now have a problem with a sticky cantilever brake on the same bike with the bad wheel hub. I have Avid Shorty center pull brakes and one side on the rear sticks when I apply the brakes. It feels like the little wire spring that runs around the base of the lever is sticking inside the base. Lets see if I can insert some images to illustrate the piece I am talking about:

Here is the spring wire - it is entering the base on the right:



Here it is where it comes around the base on the other side. I think it is sticking in the base:



Here are two views of the spring from the lever side showing it's range of motion which is the same as on the working lever. The spring is not tight in that section it moves back and forth readily as does the spring on the working side:




I have tried adjusting the screw on the base but that didn't help and possibly makes the problem worse. I also moved the pin into the forward of the three pin holes (Sheldon Brown says that increases spring tension). That significantly increases the tension but it still sticks. Also, with the pins in the forward hole, the brake springs don't stay put on the pad side of the lever. The increased tension causes them to pop over the stay (that silver looking post right by my figure tip on the left of the last photo. Has anyone experienced this sort of problem. Can I disassemble the base and clean it? Re-tension the spring somehow? Buy new brakes?

stapfam

No idea but one of the problems I found many moons ago was with regard to the Brake fixing bolt. That has to be tight but something went wrong with the bush and I had to slacken the bolt off a bit. Not a good idea so I stripped the whole unit down- cleaned and regreased where necessary and reassembled. Put it back on the bike and it still stuck. Bought new brakes- Cured.

BlazingPedals

When a canti/V-Brake arm sticks, I've found it's usually because the post (on the frame or fork) is gunked up. The arm is off, now clean up the post of rust and gunk. Buff it up with some steel wool. Then, clean out the hole in the brake arm. Lightly grease and re-assemble.

NOS88

+1 They can get real stiff with remarkably little crud in them.

BluesDawg

Agree with others that cleaning the post is probably the solution.
Just a little terminology nag - your brakes are are cantilever brakes. These are center pulls:
https://store.velo-orange.com/index.p...ull-brake.html

donheff

Wow, 50+ rocks!!!! The posts were the problem. Cleaned them up and the sticking is gone. Those posts looked fine. It doesn't take much crud to mess the works up.

Thanks for the help.

Phil85207

Ain't this a great forum?

BluesDawg

As helpful as BF 50+ can be, sometimes you may want to draw from a larger pool of knowledge on mechanical questions. The Bicycle Mechanics forum on BF is a very valuable resource. You'll recognize familiar names from 50+ among many others answering questions as well as asking them. I have learned a lot there.

donheff

Aha, I would have called them just cantilever but I had been reading up on them with Sheldon Brown. He describes three types of cantilever brakes, mine being a "traditional center pull, thus my description of them as center pull cantilevers."

Edit: just re-read it and see I called them center pull rather than center pull cantilevers. Your correction was correct

I am a bit reluctant to venture over there (although I may in the future) because I am fairly mechanically clueless. Better to get advice from a sympathetic audience over here and venture over there when this crowd is baffled.

As a side note I learned that my spring popping problem was resolved by backing out a little adjustment screw that I initially needed to tighten up to get the tension pin into the forward of the three holes.

Here is another mystery encountered in this effort. My front brakes have been squealing like a stuck pig for a year or so. I use them in lieu of a horn to warn people of my approach. I have tried all kinds of things to fix them (toe in, sanding the pads, etc). With a new wheel on there I decided to install new pads (even though the old ones were not yet done in). Still squeals.