Rear Brake

I had my bike in last week for an MOT and a new set of tyres. It passed
the MOT first time and i have had no problems up until tonight. I parked
my bike went to open the garage door and upon riding into the garage i
heard an almightly squeel, on inspection the rear wheel was locked and
it appears my rear brake has locked up. I have managed to free it so the
wheel spins but as soon as you apply the rear brake it locks again. I am assuming that the garage has done something as the rear wheel has to come off to put tyre on. I am assuming the rear brake is checked on an MOT so surely it can't have seized in less than a week.

Either the sliding pins are seized or the piston is stuck.
You'll have to take the wheel off, the caliper carrier should slide off. If it doesn't there's just enough room to get a spanner on one of the pins and you should be able to persuade it apart.
You will probably need to replace the rubber boots that the pins slide in, don't forget lots of copper slip on the pins!

Assuming you have the disc brake version sounds like

(a) the brake piston is sticky or
(b) the pin that allows the caliper side float has jammed up or
(c) the brake pads are sticking on the mounting pin inside the caliper

the brake is not too difficult to strip or work on (which is a blessing).

Other idea is that the wheel is out of alignment, though with the brake mounting plate mounted on the back axle, difficult to see how this could be.

Hi jimmy

out of interest, what did you do to `free it up`.

Do you have a disc or drum brake?

I am running a 94 model so my rear brake is drum. I spoke to the garage this morning and it was put on a rolling road for the MOT last week (which it passed) so i think that it is just coincidence and old age. I physically released the brake myself last night and will be riding without a rear brake (although it only covers 20% braking anyway) for a couple of days before i can take it into the garage. I am not mechanically sound enough to attempt wheel and brake removal (and don't have a chain splitter) so a professional job will be required. Am hoping it will be a cheap fix though.

With drum brakes the usual cause of sticking is the shaft that goes through the brake plate getting gunged up or losing lubrication.

What I'd try is to remove the brake arm that is on the splines at the end of this shaft, try running WD 40 up it to loosen it, followed by some heavier grade oil. It often does the trick, and if you do this regularly, should stop it happening again.

Hope this works for you

You don't need a chain splitter to remove the rear wheel, just undo the axle bolt (don't remove the axle), shove the wheel as far forward as possible and then you can remove the chain off the sprocket and hang it to the left of the frame/wheel.
The drum break is a singe too, undo the bolt from the small fixed arm (there is a safety pin to remove first) and then remove the brake arm at the point where the lever on the drum brake and the arm connects by the back wheel. This type of bolt is a brake adjuster too...for reference.

Now place yourself at the rear of the bike and with support under the wheel (wedge your foot under it) take the axle out and the wheel will come away very easily.

With the wheel off, slide the drum out of the wheel. You may have to wiggle the brake lever to fully retract the pads off the wall of the wheel.

You will get a weee bit dirty - but you don't need to be technically minded really.

Cleaning any gunge will be a singe using a cloth/toothbrush and brake/clutch cleaner (an aerosol spray available at all motorfactors). Grease the moving mechanism, but do not get any grease on the pads or the surface that the pads come into contact with.

Re-build exactly as you removed - but in reverse.

Hope this saves you a garage bill.

Good Luck chap

G-T

Thanks for the advice but in the end i was too chicken to atempt a wheel removal and a brake stripping. I took it too my local dealer who charged me £45 for a two hour jobs. Basically the pivot from the brake pedal was siezed so it was just a case of stripping cleaning and re packing with grease.