If I am to fit new brake pads, in which locations should I apply the copper grease?
I have the pads (which have lose fitting/floating thin metal shims behind them)
The pads appear to only rest on a ledge on the caliper towards the front of the bike and run on a pin/bolt towards the back of the caliper
I assume I apply some copper grease to the smaller pin/bolt in the image below (the one that's done up to 18Nm)
But do I also use it anywhere else?
I do seem to have a little noise coming from the rear brake unit, which seems to be notable only a very low speeds (about 10mph when coming to a stop) Like a knocking sound.
It's hard to identify it.
I've just been in the garage and been rocking the bike to and fro a few inches, and I can hear a clicking sound as I roll the bike back and apply the brake, then rollthe bike forwward and apply the brake.
This appears to be the calipur unit moving a millimeter or so in either direction.
I assume it's normal for the whole rear calipur unit to move/flex "rotationally" when the rear brake is applied, as it's kind of floating on it's bolts is it not?
The MOT guy did mention it yesterday and I assured him it was all torqued up correctly.
Roll the bike forward, apply the rear brake and the rear calipur (as it grips the disc) moves a little (a millimeter or two) clockwise and springs back when the brake is released.
@tempest, the rear caliper is fixed but can move side to side.
make sure it's been fitted properly when the wheel was last off - ie the locating lug slots into the recess in the swing arm so it cant move.
sounds to me like the rear disc could be warped a bit.
might be worth taking it off and having a look at it - lie it on a piece of glass or summat.
a new rear disc wont cost much
regarding copper grease - a thin smear applied between the backplate of the pad and the thin anti-squeal plate will do the job
You do not have to say anything. But it may harm your defence if you do not mention when posting something which you later rely on in quote. Anything you do say may be ripped to sh*t.
I only had the wheel off a couple of weeks ago (new valve and rebalance) and put the wheel back on, and 100% I'm "In the groove!" re the swing arm slot.
Everything torqued back up.
This odd occasional noise started when I fitted a new disc and pads.
To be honest, I've probably not really even done 100 miles since the pad/disc change, so it's all very squeeky clean and new still. I have wondered if it's still bedding in.
I just went outside to visually check everything & ran up and down my short road (well, I didn't run, I rode the bike!) got up to about 30mph and brought the bike almost to a ful stop only using the rear brake, and all perfect. No noises or funny knocking sounds at all.
And yet, another time as I come to a stop I'm sure I can hear some funny knocking as I slow down from the rear calipur.
I'm confused.
Re disc warp. I actually set the disc up at work and reground both sides of the disc dead flat on a rotary attachment on a surface grinding machine, and took out all dips/ridges etc before fitting new pads.
The disc still measures 4.63mm thick (after I ground it dead flat) which is above the recommended 4mm min thickness, and it's within approx .001" accuracy.
The pads appear to have an even wear mark around the disc so far (no gaps) And the disc was all torqued back up correctly onto the wheel, as for run-out, that could only be if the wheel surface (the disc lays against) was itself running out.
As I said, I just tried breaking from 30mph six times and perfect.
Very puzzling, I am still left with the thought of (it's just settling in) unless anyone else has any other thoughts.
Sounds like you have glazed the pads ,remove and rub them on some 120 grade wet n dry on a flat surface then refitt and take it easy on them for a few miles.
