Corrosion on Avid BB7 brakes
 

I have BB7 brakes on two of my bikes and have been using them for a few years now. I like them for simplicity an ease of use and maintenance, but these brakes have not been trouble free. After few winters the pistons on these brakes seized up so bad that it was impossible to turn them and do pad adjustements.
Just today I had to take the calipers off the bike and then disassemble them completely for some serious cleaning. Taking them apart was easy but I was amazed how much crud and corrosion was inside, it took me some time to scrape and clean all the crap out of there and then lube them and get everything moving smoothly again. Assembling them back together was a little bit more awkward because of trying to hold the little spring on the inside under tension while tightening everything back together. These brake calipers are not sealed very well from elements and salt water has a way of getting inside and eventually everything will just seize up and stop moving...I've also had problems with hydro brakes many years ago,, seals would corrode and fluid would start leaking. At least BB7 are easier to work on and no fluid to mess around with. One of the reasons why I love riding my fixed gear bikes in winter is because there is no maintenance and even if brakes stop working I can still stop.

Only issue I've ever had is some surface rust on the mounting bolts. Never had any issues with the Shimano mechs on my high-mileage bike either.

How often do you clean the bike? I always give mine a good going over after the salt is off the roads.

If you ride in the Winter when/where they salt roads, the salt will destroy stuff pretty quickly. Regular hosing off helps, but finish with a Spring cleaning consisting of a heavy duty washing of all places salt can get to.

Use of products like LPS-3, and other oil/wax products during assembly also helps prevent salt water from wicking into the crevices between attached parts.

As a scuba diver, I can tell you that it's best to remove salt while parts are still wet. Once salt dries it's much harder to re-dissolve and remove.

BTW- so far, I haven't found anything that's an aid to salt removal (other than lots of water). When doing my annual dive equipment service, I end up having to toothbrush off dried salt deposits.

Maybe someone here knows of something that can be added to rinse water to speed salt removal.

To be honest, I'm not sure what's in the salts that are used on US streets.

But, I'd be interested to see what would happen if EDTA was added to water used to wash bikes.

Most cities use Halite or coarse sodium chloride, aka rock salt. Basically the same stuff in the sea and on your table. Some cities are moving away from salt to eco friendlier (or claimed to be) organic deicers, but I have no idea of the chemistry. Here in NY it's mostly salt.

I don't know about lime sacle removers, having never tried them for salt.

EDTA is a chelator that sequesters metal ions out of solution.

Salt is an extremely broad term that includes metal ions.

EDTA/EGTA or similar chelators may help.

Yep, I think you're right about rinsing salt off before it dries . When I took my brakes apart I've noticed there was a heavy build up, like crust which was very hard to scrape off, I couldn't even get my new pads in there. I never rinse or clean my bikes during winter, I always wait until spring. I learned my lesson, and from now on I am just going to rinse it with water more often and make sure all the salt is out of there. Our city is using some other chemicals mixed with salt , it's bad stuff and seems to be very corrosive.

This was a timely thread. I was just changing out my winter studded tires to gravel grinder tires about an hour ago and noticed how much off a beating my BB7 took over the winter. I guess I will be taking them apart and giving them an overhaul.

It's a good idea to clean salt off cranks at the very least. Back in the 70's/80's, when I was leaving the cleaning to the end of the season, I went thru 6 Shimano & Campag cranks. They would just break, usually in the fall, from the salt eating into or weakening the cranks. When I started washing off the cranks each day, the breakage stopped, at least until last year, when I broke a SRAM Omnium crank.

When you look at the cross-section of the break, you'll see part of the aluminum is dark, where it had been cracked for a while, and the rest was shiny aluminum, the portion that had just broken.

Luis

think they just released a new version with stainless steel Bolts .. that would fix it.

corrosion of the aluminum may take Painting it again.