wallHax

Hey,
So to my horror, on my commute today i noticed, that my rear brake was unoperable/stuck/frozen (-8°C). I had to properly hamfist the brake lever (shimano bl-400) to get some movement out of it, to the effect, that it just "moved" the calipper sideways to constantly rub at the rim.

The rear brake was never great to begin with(sidepull weinmanns, new ultegra pads, sub-opitmal cable routing on the mixtie, non compressionless housing).

Any tipps on how to deal with that issue?
I was considering new dual pivot calippers, (and compressionless housing), but the rear brake routes from below, so thats tricky..

KR

maddog34

store your bike in a heated area that allows any water intrusion to dry before you use the bike again... ? your bicycle will thank you!

grumpus

That's a common cause of frozen rear brakes - water gets into the end of the upturned cable casing, and it doesn't drain out again. You could try some of those cable end ferrules that are supposed to seal the cable against water and mud. I'd probably just keep an eye on the brake action, and replace the cable when it started dragging .

Hondo6

Dunno if your mixte frame has a rear brake bridge on the mixte tubes or not. But if it does, you might consider a center-pull brake installed on that with cable running down the mixte tubes, like this Univega:

https://store.bicycleczar.com/50cm-U...p/09220030.htm

FBinNY 

As mentioned above, the likeliest cause is frozen water on the cable. There's no fix except for heating the cable. If the circumstances allow, bring the bike indoors and play games on your cell phone for a few minutes while it thaws.

However, it's preventable by oiling the cables when the bike is setup. Some have also had success using things like "bassworms".

OTOH I'm curious about you saying you got the brake to move to the side. That might imply that the issue was within the caliper itself. That's very rare, but if this happens again, start by squeezing the caliper directly. This will free the jam if it's at the caliper, or confirm that it's in the cable.

zandoval 

Sticky cables in cold weather is also a motorcycle problem. Small can of WD40 might come in handy. Near seawater its common to shoot Marine Grease into the cable housings to delay rust formation. In cold weather that same grease can be a bugger...

Andrew R Stewart 

We saw a lot of this with winter commuters both in Cleveland here in Rochester. Add in the salt spread about the roads and after a number of freeze/thaws of the rear brake cable the rust would set in. The absolute best way to avoid (besides not riding in those conditions) is to ramp up the maintenance. Service (remove and lube with a heavy grease) the cables just before the freezing season and once or twice during. Adding a drop of oil at the cable casing ends every few weeks also helps. But it is getting the grit/grime/salt that gets in out and using a thicker lube to coat the cable in the casing that it the real trick.

Some calipers can have the anchor bolt and threaded barrel adjuster trade places and the casing loop enter the caliper from above. If you have segmented cable casing along the (dropped) top tube(S) replacing it with full length casing can also eliminate water entry ports.

I had a good friend that was commuting through the winters here years ago and he found that keeping the bike from going through freeze/thaw cycles helped. he would keep the bike in the shop's garage during the day and on his back porch at night. But he still would need to do maintenance a few times each winter on the cables. Andy

FBinNY 

With respect to Andy, my experience is that heavy grease in cables is a poor trade off.

While it helps prevents water intrusion it also thickens and makes cable movement sluggish in cold weather. So, while hard freezing is prevented, the cable action is poor and brakes ten not to release well. This is much worse in modern brakes which have very light springs.

So, I suggest a light grease such as lubricate 630aa, or oil.

79pmooney

I rode in similar conditions way back when in Ann Arbor and Boston. I don't recall doing more than oiling the cables or maybe greasing them with the rather thin Phil Wood grease. I do recall that every cable entrance and exit out of the housing was a potential problem area and gave those spots more attention.

And on that note, I always used full length housing for the rear brake. I hate the exposed runs along the top tube. Every transition is a weak link on a winter bike. I'm guessing your cable is bare as it runs between the mixte tubes. Can you replace that with continuous housing from brake lever to the final housing exit? Maybe ziptie the housing to one of the mixte tubes. Going centerpull is also a great suggestion. I highly recommend the Mafac Racer brakes. Long out of production but they made many thousands. Every cheap Peugeot came with them. Try any bike coop. They last nearly forever. Work just fine with lots of play in the pivots and people are still making replacement bushing to make them like new again. I used to ride and treat my winter bike like a beater car when I lived in those cities and didn't own a car. Looked at the Mafacs maybe twice a winter.

Last thought. Your mixte cable run is probably both longer and more contorted than the usual man's bike. While both more expensive and more of a hassle, the good incompressible housing might be quite worthwhile. Likewise the best stainless steel cables with the very smooth outer surface. I think Jagwire is the brand to look at. (Fellow regulars here, help the OP out if I have the brand wrong.) I would still wipe a little oil on the cable before installing. Make it as hard as you can for that frozen water to grab anything.

Andrew R Stewart 

And I do agree with Francis in that a light/thin lube is best when only freezing temps are the problem. There are many stories about snow riding and cable sluggishness. However I find most winter riders don't do their part anywhere nearly enough. Hence my suggestion to a grease to help offer a physical barrier to water intrusion. My take is a slow to release caliper (from thick cold grease in the casings) is better than no brakes when you really need one. Andy

Velocivixen

I’m personally a fan of Phil Wood Tenacious Oil on my cables - sparingly.

Hondo6

Assuming a mixte brake bridge is present, using a rear centerpull brake attached there also means water collection in the cable housing becomes less of an issue period. With that setup, the possible entry points into the housing for water are now the brake lever and the other end of the housing - both of which are often if not usually lower than the high point of the rear brake cable housing. Since water has a very low viscosity, most if not virtually all water that might get in should drain out before it freezes. And if a trace of water does remain inside, a good coat of oil or light grease on the cable should prevent adherence.

JohnDThompson 

When I put dual-pivot calipers on my daughter's 3-speed, I swapped the mounting location of the cable anchor and barrel adjuster to accommodate routing from below.
N.B. when the cable is routed from below, the housing can collect water in the dependent loop, which can lead to rust or ice that impedes cable movement. I always use grease (either injected int the housing with a grease gun, or smeared on the cable itself) to prevent this.

oldschoolbike

This is why I rode a fixed gear in the winter. Everything moving is also self cleaning. I did use a front caliper brake for better days, which was probably OK only because both cable ends faced downward.

oldschoolbike

wallHax

Thank you for all the suggestions.
To adress some questions:

• No, there is no brake bridge where one would usually put a centerpull. Can i fashion something out of, i dunno, steel, aluminum? I would much prefer that solution, as it would shorten and straighten the cable run. I do have a set of motobecane centerpulls, but i fear the straddle cable is a bit short to route past the seat tube, which makes me wonder where i can get a longer one?
• The cable run is fully housed. No exposed cable, except for the end where the calipers "squeeze"

Thanks !