brake alignment ...... squeak

[Slowbee]

ok so I washed Mr RacerT over the weekend.

 

Then I spoted a glitch, maybe its a biggie, maybe its newbie panic for nothing.

 

But here goes, on the front brake. It looks like the big steel disk attached to the wheel (rotor?) is rubbing against the big thingie attached to the fork that allows the gadget that holds the brake pads to be attached (caliper housing?).

 

How do I correct this rubbing as it is part of the squeaking hassles I have been having? It also seems to be why the wheel does not spin so freely.

 

oh yes they are juicy sevens.

 

any help?

 

[Tumbleweed]

is the rotor true?

[KevinV]

is the rotor true?

Mine isn't after yesterday's crash! Slowbee, if the rotor IS true is it rubbing against the brake pads or against something else?

[Slowbee]

Hr, just checked, yes it is.

[Slowbee]

Rubbing against the thingie that holds the brake calipers onto the fork

[Johan Bornman]

That's par for the course with disk brakes. They have no mechanism that retracts the piston after braking, it just relieves the pressure on the piston and it therefore more or less stays in contact with the disk.

It's the same with cars, motorbikes and airplanes that use disk brakes, evident from soft squeaks when you drive past a wall that reflects the sound back to your car.

You can attempt to re-adjust your calliper (thingy that goes over the round metal pizza thingy) but don't expect miracles.

Live with it.

[KevinV]

Slowbee. I don't know the juicys very well but sounds strange. I would take it to your LBS and let them have a look.

[Tumbleweed]

did you remove your front wheel before you cleaned the bike?

[Bike Mob]

If the Caliper is rubbing on the rotor you cant just leave it like that.

 

Those juicy 7's have a tri align system, that is even more difficult to align than a standard system!

 

Loosen the whole system off, and tighten each bolt incrementally, sometimes holding the brake on will align them decently, but don't count on it.

 

Take your time, those funny crescent shaped washers can pack down skew if tightened too hard all at once.

 

[AndreZA]

If the Caliper is rubbing on the rotor you cant just leave it like that.

 

A caliper will never rub on a rotor but the other way around. and it will actually touch the pads inside the caliper, not the caliper itself.

 

The best way that I use is to place a small torch that can stand on it's rear end by itself and place it below the caliper so that you can see the space between rotor and inside of calliper properly. Now find the two extremes of the rotor, ie the most inward and most outward "wobble" and adjust the caliper so that neither touch. If it isbent so bad that it still touches then heat it it on a solid plate stove with a heavy pot filled with water and let it cool down on there aswell. Otherwise replace it.

 

 

[Daxiet]

I have Juicy 3.5's (Because they're on a Scott, the Juicy 3 becomes a 3.5). They are buggers to calibrate and are on my list to replace as soon as possible for this reason. Riding in a long race hearing them rub away really ticks me off (why bother having bearings on your wheels when your Juicy's provide 24/7 friction). Enough complaining.

 

No the rotor should not rub against the bracket attachted to the fork holding the caliper in place. Mine comes very close to the bracket, but not close enough to rub. There are many ways you can try fiddling about to get the rubbing gone, but they depend on what happened during your cleaning phase.

 

Did you remove the rotor in the "bathing" process?

 

If rubbing against the bracket, not the caliper and not the pads, then the Juicy calibration technique will be fruitless as this process only sets the angle/spacing of the caliper/pads around the rotor, no effect on the bracket.

 

If you can't move the bracket any further away from the rotor,  you do not have a lose hub and your axle is seated correctly in the fork, then your rotor must be slightly bent outwards.

 

 

[dirtrider]

And if you had Shimano brakes then the brake pads will return after you have braked ! Those little plates between the pads that we all throw away after the first pad replacement does just that . Now back to your problem : Do what Mampara said but add some potatoes to the water , that way you not wasting energy .

[Johan Bornman]

And if you had Shimano brakes then the brake pads will return after you have braked ! Those little plates between the pads that we all throw away after the first pad replacement does just that . Now back to your problem : Do what Mampara said but add some potatoes to the water ' date=' that way you not wasting energy .[/quote']

 

Sorry, but I disagree with you on the springs.

 

Those little springs are not strong enough to push the piston back. All they do is stop the pads from rattling and perhaps taking up some incidental slack. But create space for the disk they don't.

 

I absolutely agree with you on the potatoes though.

[Daxiet]

I have to agree, the little spring in between the pads if far to weak to force the pistons back.  The Avid's have the same spring idea as the Shimano's incidently.

 

Potato idea - Eskom would appreciate this move, can't waste any energy these days.

 

[Slowbee]

no man okes - you not understanding the problem.

 

i will try and explain in my limited technology terms.

 

On the fork is a bracket. Attached to this bracket is the housing for the brake pads etc.

 

It is against this bracket that the rotor is rubbing, and might have something to do with the alignment story. The rotor is true.

 

Do you just undue bolts and try align things or is there some mystical initiation ceremony involved?

 

[dirtrider]

Oooooh IC . Your axle on the hub is not loose ? The bolts that holds the calipers in that position have got no adjustmunts .