Rear breaks getting stuck.

Gautama

Hi,

The rear breaks of my bike are getting stuck when I use them; i.e. when I use the brakes, they close on the wheel rims but don't release fully. There's still contact. I've been told that it's because dirt is getting caught on the spring that connects to the two arms of the break. Given how filthy the roads are these days after the gritting, this seems to be a plausible explanation.

What is the best way of "getting in there" to remove the dirt?
Is there an aerosol of air that can be used to blast the dirt out of there before I grease it? I've seen such aerosol for cleaning keyboards, etc.

I only had the bike in for a service a few weeks back so don't fancy taking it in again so soon.

Thanks.

CheGuedara

If its just cleaning the brake that's required, give warm water and wash up liquid a go and use an old toothbrush to get into the nooks and crannies and wash off with just water. (worth a go without having to go out and buy MucOff cleaners)

TBH, it's very likely that the brake cable and/or housing is after getting cack into it and causing the cable to get caught or stick - check that out too.

Oh yeah - and while you're cleaning the brakes, sure why don't you wash the whole bike?

gman2k

You could remove the brake from the frame and steam clean the entire caliper, and then relube the mechanism,
or remove wheel and brake blocks and thoroughly spray with WD40, whilst operating the brake lever until free, then wipe clean and relube with a light oil.

Run_to_da_hills

I would recommend cleaning / replacing the rear brake cable, it could be rusted up or kinked.

bcmf

As with Run to da Hills above complete replacing of the entire cable and housing will cure this. Inside the housing gets worn out and and stops the cable from returning when you release the the brake lever.Get both front and back done should do no harm.Should only cost a couple of quid at lbs if you cant do it yourself

paddyduc

If it's just been serviced it hardly needs new cables. The brakes are more than likely off centre or there is an imbalance in the spring pressure left to right.Are they v brakes or caliper?

doozerie

Another possibility is that the wear in the brake pads is such that the pads themselves are snagging on the rim. If this if the case then either repositioning or replacing the brake pads will sort it.

To systematically narrow down the root cause though you need to isolate the brake lever (another possible culprit but probably least likely), the brake cable, and the caliper. If the calipers are Shimano, release the quick release on the caliper itself so that the arms splay out as far as they can go (if it is Campag, the release is on the brake lever). Pull and release the brake lever to see how freely, or not, the calipers open and close - don't pull the lever far enough to make the brake pads meet the rim as if the brake pads are the problem they'll skew the results of this check. Check the calipers themselves just by squeezing the arms together by hand and releasing them again - it doesn't eliminate the cable from being a factor but sometimes helps you to spot a cable issue too. If the calipers seem okay, then squeeze the calipers closed by hand and while holding them closed pull and release the brake lever to see how freely it moves - again the cable can interfere with this check but usually this check shows up serious cable issue too if they exist. Removing the wheel gives you a greater range of movement in the caliper to carry out these kinds of checks.

The most effective way to check the cable itself is to release it from the caliper, hold the end of it in your hand, and pull and release the brake lever. As you pull the lever the inner cable will be pulled into the outer housing, after you release the lever pull the inner cable back out by hand and feel for roughness. It is also easier to check how freely the brake lever moves once the cable is disconnected, and also take the opportunity to check the caliper again.

If the brake caliper is the problem, and you are comfortable with working with relatively small parts, then remove the caliper from the frame, dismantle it, clean it up, re-grease it (a light grease is arguably better than oil but both will work), and put it back together. It's usually simple enough as calipers are not complex, but just make sure that you have a good look at how it all fits together before you dismantle it. Take staged photos while dismantling it if you are really worried, and also use the other caliper as reference when putting it back together.

p15574

I had problems like this and while they're not completely fixed, the thing I found most effective was getting some oil to run down the brake cable. This was after disassembling/cleaning/oiling the brake mechanism itself to no avail. This would be the next best thing to replacing the cables, and cheaper too.

The bike had previously been left out in the rain for the winter and the cables must have rusted.

f1000

I have had the same problem due to the leftover grit on the roads. Had to replace the rear calipers and buy a new cassette & chain. I have also noticed that my pads dont last as long.

C'mon DCC get the road cleaners out!

Canis Lupus

I've got a Claude Butler and the back brake is forever doing that and I seen on the net someone complaining about the same thing on the same model. I've let the bike get filthy the last couple of months and it's gotten terrible. Tomorrow I'm taking it to be powerwashed then I'm going to scrub it to within an inch of it's life and finish off by oiling the **** out of it.

doozerie

If oiling/greasing the pivot points doesn't do the trick, or doesn't last long, then slacken off the bolt(s) holding the caliper together at the pivot point(s). Slacken them off too much and the arms will rock (i.e. the entire bike will judder/rattle when you brake), so adjust slightly and test and repeat if necessary. If there is some sort of threadlock on the bolts already, then this will effectively dislodge it so make sure to regularly check the bolts afterwards to make sure that they don't work their way loose over time.

jimm

Canis Lupus wrote: »

I've got a Claude Butler and the back brake is forever doing that and I seen on the net someone complaining about the same thing on the same model. I've let the bike get filthy the last couple of months and it's gotten terrible. Tomorrow I'm taking it to be powerwashed then I'm going to scrub it to within an inch of it's life and finish off by oiling the **** out of it.

Do not go anywhere near a powerwasher with your bike. Anything above a gentle spray with a garden hose should be avoided unless you want to f*** up your BB, bearings, etc.

kona

jimm wrote: »

Do not go anywhere near a powerwasher with your bike. Anything above a gentle spray with a garden hose should be avoided unless you want to f*** up your BB, bearings, etc.

Good advice. Your asking for trouble powerwashing anything. To clean a bike, a brush, a rag and some muc off will do the job, no need to drive water into every bearing and crevace in the bike.

OP, Id replace the cable, both inner and outer and see how it goes from there. Most of the time the cable is the issue.

If its a V-brake you will need to balance the arms, as a weak spring wont return the brake arms after you use them.

If its a road calliper, and this seems to be a issue with them when they are neglected, you will have to spend a while with some penetrating oil and force to try and free it up. If you have no luck Im afraid the easiest/less stressful way is just to replace it.

I would not use WD40 as any sort of lubricant on a bike. If you are going to use it, make sure you have some light oil to relube the pivots with.

Canis Lupus

jimm wrote: »

Do not go anywhere near a powerwasher with your bike. Anything above a gentle spray with a garden hose should be avoided unless you want to f*** up your BB, bearings, etc.

I had intended to use it selectively cos I have read here before that it's not good. But it's so so cold outside I can't face doing it the normal way

kona

Canis Lupus wrote: »

I had intended to use it selectively cos I have read here before that it's not good. But it's so so cold outside I can't face doing it the normal way

Remember that when your replacing Bearings , its not *that* cold!

Golfanatic

just take them apatrt thouroughly clean them then retension the springs this will do it. if you could try just putting a chain oil in the cables

IM0

bcmf wrote: »

As with Run to da Hills above complete replacing of the entire cable and housing will cure this. Inside the housing gets worn out and and stops the cable from returning when you release the the brake lever.Get both front and back done should do no harm.Should only cost a couple of quid at lbs if you cant do it yourself

this ^

boege

Found same problem with both brakes on my bike (Shimano Sora) today. Quickly ruled out cables. Managed to free the front brake with chain oil but had to do a complete strip-down of the rear brake.

Suspect salt/dirt from cold weather has set up some chemical corrosion between the aluminium calipers and the steel washers. Sanded all the joining faces with fine emery paper and regreased all the surfaces.

All working now.