Squeaky rear end

[markso]

The bike, not me

Removed my rear wheel last week to give everything a good clean, but I now have a loud but intermittent squeak from the brakes (Juicy 3's). It's not there all the time, so I'm not sure what I've done?

If it was the alignment of the rotor, wouldn't I get the noise all the time, or is it to do when the rotor gets warm?

The pads don't look worn out, so I don't think it's that.

Anyone got any ideas?

Mark

[thistle]

Your rotor is warped. Only slightly, and not enough to be a problem.

Flip your bike upside down, loosening the QR, turn the nut of the axle 1/8 turn with a cone spanner then tighten quick release and you'll probably find it's different (rubbing more or less). Keep fiddling to see if you can get it to stop.

Russ' method is undo the QR with the bike the right way up, wiggle the frame then tighten up again but it didn't work for me.

Juicy 3s are notorious for squeaking when you brake, with other brakes it might rub but you wouldn't hear it. Things you can try are cleaning the rotor, give the pads a light sand and make sure all the bolts for the rotor and caliper are done up tight.

[markso]

Cheers Thistle,

I had tried Russ's method when out, and it worked for a while, but then reappeared.

Will give your method a go.

Mark

[Russ]

Is the noise when you are riding along or is it when you apply the brake?
Does the wheel spin freely?
What did you clean it with?

The Russ trick is to ensure your wheels are correctly aligned in the frame/forks every time, that way you can then correctly adjust the brake caliper alignment.

[markso]

Hi Russ,

I hadn't cleaned the rotor as it was pretty clean. The squeak is when riding, braking quietens it down. The wheel was running freely before the ride and only started about 20 minutes in.

I'll have another look at it though.

[Russ]

If it's down to the brake then, at some point during the wheel's rotation a pad is touching the rotor.

If you lift the bike up at the back/put in the stand and spin the wheel then look at the top of the disc brake caliper, most likely you will see the spring move on a regular basis. You can see the top of the spring looking down into the caliper it's that silver bit in the middle.

Could be a sticky piston
crap between the pads
bend in the rotor
Caliper needs aligning

Bend in the rotor you will see as you spin the wheel, now most rotors have a slight kink in them but unless you are a serial brake dragger on big descents then usually it won't be enough to worry about so:

1: Do the Russ trick with the wheel so you know it is properly in the dropouts.
2: Spin the wheel and see if the rotor is catching anywhere
3: Loosen the top 5mm Allen bolts on the caliper these are the ones that are sort of vertical. Just undo them 1/4 of a turn.
4: Waggle the caliper gently with your hand - the washers beneath the caliper get crap in them so seize a bit, waggle helps loosen the carp there.
5: Pull your brake lever and hold
6: Tighten up the bolts again.
7: Spin wheel and see how it is.
8: Pull brake lever a couple of times and see how it is.
9: If still dragging a bit goto 3 a couple times

If it still wont adjust out then it's most likely a really warped rotor, or even more likely a sticky piston, uneven pad wear will be a good indication of this.

[markso]

Hi Russ,

Thanks for the info, will hopefully get it sorted tomorrow.

Mark