Brake Pad Retaining Clip gone...

[Ade B]

When I got new tyres the fitters said the front brakes were missing a pad retaining clip. I purchased a new one and after a bit of scrambling around on the floor, fitted it with the wheel in situ today. It clipped in and matched the other side in appearance but didn't seem to have much pressure on it

Took the bike out for short ride to check the changes to the carbs I'd made, and on returning home, the clip has gone...

The brakes work OK (for 1977 ATE brakes) they do stop the bike eventually. They squeal a bit, which I suspect is due to the clip missing... do I need to take the thing apart to fit the clips?

[gspd]

That clip is there so the inner pad doesn't fall out when removing the wheel.
It serves no other purpose.

A light coat of high temp grease on every surface where the pad backing plate contacts the caliper always eliminates squealing.
BTW - This works for every vehicle that has squeaky brakes. No more squealing, money back guarantee.

Adjusting the caliper(s):
Turn the eccentric bolt (that tilts the caliper) in and out while applying some pressure to the brake lever. You'll feel a point where the eccentric bolt will no longer turn either way with the brake slightly applied, that's where you want it. This method is much more accurate and gives better brake performance than BMW's instructions which consisted of making paint lines across the disc surface and spinning the wheel while applying the brake lightly and adjusting the caliper until the pads scuffed the lines evenly.

[Ade B]

Thanks for replying gspd. Good to know it's not a safety critical part...

I've a few other things on the list to sort before tackling the brake squeal but will get there eventually.

Cheers

Ade

[SteveD]

...A light coat of high temp grease on every surface where the pad backing plate contacts the caliper always eliminates squealing.
BTW - This works for every vehicle that has squeaky brakes. No more squealing, money back guarantee. ...

My K1200R has squeaky brakes. I tried that method...limited success. The local very good and very experienced independent BMW mechanics (known then since the 1980's) didn't like it at all!!!
What did reduce the squeaking was a fast blast thru the mountains, especially after the long windy downhill section where braking was heavy. The brakes went quiet for a day or so. Squeak returned.
I have another wheel.tyre/discs that doesn't squeak so I'm thinking it's not the calipers or pads? I'm wondering if it might be the wave washers of the floating discs? Is that a possibility d'ya think? (apologies for non airhead q.)

[gspd]

My K1200R has squeaky brakes. I tried that method...limited success. The local very good and very experienced independent BMW mechanics (known then since the 1980's) didn't like it at all!!!

Did you ask them why?
Are they worried a smidge of grease melting onto the wrong spot could cause a disastrous brake failure and you'll drive off a cliff and die? It won't, it'll just burn off. It's obviously more profitable to just sell new discs and pads, this usually stops the squealing at least temporarily.

I have another wheel.tyre/discs that doesn't squeak so I'm thinking it's not the calipers or pads? I'm wondering if it might be the wave washers of the floating discs? Is that a possibility d'ya think? (apologies for non airhead q.)

The fact that your other wheel assembly doesn't squeal with the same pad/caliper setup is probably due to minute differences between the assemblies altering their harmonic resonance. I've heard many floating discs/wave washer set ups rattle, but never heard them (or of them) causing a squeak.

I've literally cured every chronic brake squeal I've ever heard on a huge array of vehicles with this method.
Many were vehicles still on warranty and the customer was told by all the service reps at their dealership and 'head office' that the squealing is normal; "high performance brakes squeal", "you're not braking hard enough", "they all do that" "metallic brakes always squeal", etc. etc I've heard every bullshit excuse in the book.

Remove your squealing pads and examine their backing plates VERY closely, you'll see a shiny spot somewhere on the backing plate where it contacts the caliper. This shiny spot, however small, is where there is metal to metal contact (pad to caliper) and is causing the squeak.
Lightly chamfering the outer edges of the pad where they contact the disc before re-installation is also a good idea.
If your bike was here, I guarantee I'd fix your squeak in 5 minutes.



Keep in mind that many vehicles have wear indicators on the pads that deliberately scrape on the disc (like nails on a blackboard) to remind you that it's time to replace the pads.

[SteveD]

Remove your squealing pads and examine their backing plates VERY closely, you'll see a shiny spot somewhere on the backing plate where it contacts the caliper. This shiny spot, however small, is where there is metal to metal contact (pad to caliper) and is causing the squeak.
Lightly chamfering the outer edges of the pad where they contact the disc before re-installation is also a good idea.
If your bike was here, I guarantee I'd fix your squeak in 5 minutes.

Cheers, I'll have a closer look! Already tried the chamfering.
Off bikes for a few more weeks due to a knee injury, so testing might need to wait.