Rear Brake Noise

[Crossrodes]

Awhile ago I said that I had some very disconcerting rear brake noise.  It actually sounded like metal on metal.  So I ordered some new shoes anticipating that the shoes were worn out.  Today I removed the rear wheel and found the brake shoes to be in good shape as was the drum.  So I don't need to replace the shoes.

But why do I have such ugly noise coming from the rear brake each time I apply the brakes?  The Clymers manual says that 85 on had a design problem and recommended a rubber damper for one of the springs.  But my bike is a '79.  So has anyone any idea why it makes such a terrible noise each time the rear brake is applied?

[Mike V]

Mike,

What kind of noise? Crunching, grinding, knocking?  Does the noise go away shortly after applying the brake or throughout the rear braking phase?

Are the rivets on the hub (driving dog) to wheel connection in good shape?  Take a close look at the backing plate, general assembly, return springs and anchor pins for wear.  Splines?

Sorry, more questions than answers.

[Crossrodes]

Mike I'd call it a grinding noise (metal on metal) and it is present when the brakes are applied.  I'll take a look at all those components hopefully tomorrow.

[Crossrodes]

Let me change that...I'd call it a squealing noise but much louder than your normal brake squeal.  I checked the rivets and splines and they are good.  I'll check more tomorrow.

[Luca]

Is the noise mostly present the first few times you apply the brake on a ride, or will it make the noise even after several miles with some stop and go involved?

Is the brake especially grabby when it makes this noise?

Does it seem to be worse in humid weather or after it has rained?

[Crossrodes]

Luca the noise is there each time I use the brake.  The back brake has always been grabby even before it started making noise.  But...my definition of grabby may not be the same as yours...I am used to ABS brakes on my other bike.  Unless I am really careful I can skid the back wheel really easily when I apply the rear brake.  I thought that was just a quirk of the R65.  I haven't ridden the bike in rainy weather this year so I don't know if it is worse.  I live on the West coast so the weather is usually humid here.

[Crossrodes]

Hey Luca.  I see you live in Providence.  We spent some time there when we were sailing.  We have old sailing friends who used to live there.  They are also bikers...Cathy and Conrad Johnson (they now live in Florida).  They will be visiting family in Providence in the next few weeks.  By any chance do you know them?

[montmil]

If the brake shoes are glazed, perhaps a swipe with some 100 grit might quiet them down. Could do the same with the drum. Remove all grit and swarf before reassembly.

Inspect the brake drum for any evidence of scoring due to metal-to-metal contact. May be a brake hardware component coming into contact with the drum.

This idea may be too far out, but I would also check the brake camshaft where it passes through the rear housing. very slim chance it may be worn and chattering when brakes are applied.

[smiley=2cents.gif]

[Crossrodes]

Today I did the inspection of the components, greased what had to be greased and de-glazed the drum and shoes.  They were VERY glazed.  The other components looked fine.  

After I reassembled everything I took the bike for a ride.  The squealing is gone...from the back brakes anyway.  

So thanks for your input guys.

The next job will probably be de-glazing the front brakes.  They squeal but not nearly as bad as the back brakes did.