Screechy brakes!

[Raven]

Ever since Sunday, after riding through all sorts of sh*t (weather, small floods etc) the front brake has been maknig a god awful screeching noise, almost like metal on metal. The discs don't appear to be scored. I gave them a hose down with cold water then covered the discs in brake cleaner and squirted aload into the calipers (with them still on the bike), but that hasn't worked either.

Any ideas? The noise is driving me nuts and almost everyone turns their heads to look at me when I'm stopping for traffic lights etc

[Steve T]

Check that you've got some friction material left on yer pads - sounds a bit like metal on metal from this distance .

You should be able to see a good gap between the pad backing plate and the disc - a sign that there is material left.

Riding through the sort of crud you describe can increase pad wear by an extraordinary rate - you did the right thing by washing them out with cold water. But if you've no friction material left, no amount of washing is going to make the noise go away.

Just my ramblings.

Steve T

[wheeliebin]

Your calipers sound as though there ready for a quick clean, coppergrease the pins and smear a little on the rear of the pads (Not the fricton material). The squeal is mostly caused by the pads vibrating.

Despite the name, 'Brake Cleaner', it shouldn't be used for general washing. It's a fast drying solvent designed to strip oil and grease away.

[BuckarooBanzai]

As SteveT says, check those pads pronto! If there's no meat left on 'em, you'll FUBAR your disks in no time.

[Raven]

Check that you've got some friction material left on yer pads - sounds a bit like metal on metal from this distance .

You should be able to see a good gap between the pad backing plate and the disc - a sign that there is material left.

As SteveT says, check those pads pronto! If there's no meat left on 'em, you'll FUBAR your disks in no time.

They seem to be okay to me, still just a beginner to bike mechanics/maintainance though. I will have to pop round a mates to get a second opinion on how much is left. If the pads are running low, won't the brake fluid level be getting low? Out of interest, roughly how long should pads last on a 650 TA? These pads have only done 3200 miles and I'm not really a heavy braker...

Despite the name, 'Brake Cleaner', it shouldn't be used for general washing. It's a fast drying solvent designed to strip oil and grease away.

Oh cock . Shouldn't have done any harm should it?

As an aside, when I first hosed them in cold water the noise stopped, I hosed them down again last night and the noise stopped again, but is back, so it doesnt happen when the thing is wet

[BuckarooBanzai]

They seem to be okay to me, still just a beginner to bike mechanics/maintainance though. I will have to pop round a mates to get a second opinion on how much is left. If the pads are running low, won't the brake fluid level be getting low? Out of interest, roughly how long should pads last on a 650 TA? These pads have only done 3200 miles and I'm not really a heavy braker...



Oh cock . Shouldn't have done any harm should it?

As an aside, when I first hosed them in cold water the noise stopped, I hosed them down again last night and the noise stopped again, but is back, so it doesnt happen when the thing is wet

If your brakes are binding badly and caked in muck, what can sometimes happen is that the pad remains in contact with the disk and gets worn down to metal very quickly - guess how I know?

A visual inspection would reveal this straightaway, so if you can still see some depth of pad when you whip 'em out, that's not your problem.

[MandoBear]

Hi Raven,
My guess would be that the face of the brake pads (or maybe even just one of them) has a bit of crud or fine grit adhering to the surface (sometimes it can actually get pressed into the pad surface). Your best bet, if you feel confident to do this, is to whip the pads out and just gently scrape the surface clean with something like an old Stanley knife blade (don't use any force, you're not aiming to remove any material from the pad itself) - you might even feel the edge of the blade "pick up" on the offending gritty bits. Once you've done this, put the pads back in and take it easy on the brakes for a little while, just to give them a chance to bed back in.

[fatowl]

Make sure you've actually got some friction material left. One of my rear pads disintegrated earlier this week, leaving me with metal on metal.

[Raven]

Well I took the pads out, and there is very little friction material left atall, which is a bit bad considering the mileage . Bugger me new pads are expensive . They did also appear to be caked in ****, so I took MandoBear's advice and cleaned them, and this appears to have got rid of the noise .

One thing that very close inspection did throw up, was that the brake pada appear to be very lightly touching the discs, is this normal, or is this the culrpit for the accelerated brake pad wear?

[FatFergie]

One thing that very close inspection did throw up, was that the brake pada appear to be very lightly touching the discs, is this normal, or is this the culrpit for the accelerated brake pad wear?

It is normal and shouldn't be the cause of extra wear. However 3000 miles does seem a bit quick, maybe you're a harder braker than you think? I'd put it down to the dirt but carrying extra weight will put more pressure on the pads. How worn are they, 0.5 mm left or more? My rear pads last about 5000 miles, the fronts for ever.