[bbillboyy]

Hi, guys I purchased some yellowstuff pads and new padgid disks for my 330d and fitted them Thursday afternoon I've only done 26 miles since and they are squealing real bad I heard you have to perform a heat cycle on some pads is this correct with yellowstuff pads? And if so how do I go about doing it correctly any help would be appreciated as its doing my head in.

[parapaul]

Relax

I had exactly the same problem with a set of Red Stuff pads. As soon as you're through the bed-in coating after a week or so, it's all fine.

[bbillboyy]

So last night I had done just over 100 miles with the pads so decided to heat cycle them 10 runs from 60-10 about 80% braking efficiency let it cool for and hour and done the same again I heard this was supposed to stop squealing and make braking alot better, braking is alot sharper but the loud squealing is still there any reason for this?

[Drrncour]

Not enough copper grease on the rear of the pads?

[DocD]

It is very very easy to burn the high spots on new brakes with even moderate braking, this creates hard spots on the pads, which in turn creates uneven disc wear.

Patience is a very big virtue when new brakes have been installed; 100 miles is no distance in real terms for road car brakes.

I personally start with gentle braking from very low speed so as to prevent significant heat buildup and gradually increase the speed but keep the pedal pressure light so to allow the pad high spots to level off and form to the disc (rather than clamping the pads hard and forcing contact).

Doing it this way you will notice the contact mark on the disc gradually growing until after some time (2 - 300 miles) the entire surface has properly mated; only then do I put any loading on the brakes.

[Soul_Glo]

Originally Posted by DocD

It is very very easy to burn the high spots on new brakes with even moderate braking, this creates hard spots on the pads, which in turn creates uneven disc wear.

Patience is a very big virtue when new brakes have been installed; 100 miles is no distance in real terms for road car brakes.

I personally start with gentle braking from very low speed so as to prevent significant heat buildup and gradually increase the speed but keep the pedal pressure light so to allow the pad high spots to level off and form to the disc (rather than clamping the pads hard and forcing contact).

Doing it this way you will notice the contact mark on the disc gradually growing until after some time (2 - 300 miles) the entire surface has properly mated; only then do I put any loading on the brakes.

+1 my Yellow EBC took at least 500 miles to bed properly and then I noticed that the pad was eating the brake disc and the disc was scored so bad that I ended up replacing it. I was heavy on the brakes with 350bhp+ I needed the stopping power. The disc was an EBC standard disc though so I should have matched it better. When I replaced them with EBC Ultimax discs, even after 500 miles there was no squeal. I went easier on them too and that helped. Once had Pagid discs too and IMHO they squal like pigs. Is it an OEM Pagid? I wouldn't use Yellow Stuff on an OEM disc. Red stuff will be more than enough for your 330D even with a remap but you need decent discs to match. My two pence worth.

[mob17]

Well i'm about to fit yellowstuff pads on my 335D this Friday. So should i use the bed in process (8-10 runs from60mph-10) straight away, or wait for a few hundred miles whilst lightly braking as much as possible?

[DocD]

Originally Posted by mob17

Well i'm about to fit yellowstuff pads on my 335D this Friday. So should i use the bed in process (8-10 runs from60mph-10) straight away, or wait for a few hundred miles whilst lightly braking as much as possible?

The latter, don't underestimate just how much energy your brakes are disposing of hauling 1.6tonnes down from 60mph. The first few applications should be from 15-20mph max and gently too.

The more patient you are during the initial mating/bedding process, the better they'll perform for the rest of their life.

[mob17]

Originally Posted by DocD

The latter, don't underestimate just how much energy your brakes are disposing of hauling 1.6tonnes down from 60mph. The first few applications should be from 15-20mph max and gently too.

The more patient you are during the initial mating/bedding process, the better they'll perform for the rest of their life.

Ok i'll try and brake as light as possible during my daily drive, and then once i hit 500 miles (or when the contact patch covers the whole disk) i'll do the heavy 8-10 runs. Is this what you're saying?

How come some sites advise to do 8-10 heavy brake runs once you have new brakes? Not saying you're wrong just trying to learn more

[DocD]

Originally Posted by mob17

Ok i'll try and brake as light as possible during my daily drive, and then once i hit 500 miles (or when the contact patch covers the whole disk) i'll do the heavy 8-10 runs. Is this what you're saying?

How come some sites advise to do 8-10 heavy brake runs once you have new brakes? Not saying you're wrong just trying to learn more

Some old school mechanics will tell you to give them some heavy use to bed them in, they were probably told that by other old school mechanics that taught them; they were misinformed, all that happens is the small percentage of pad and disc that are in contact with each other will burn and glaze. (former reporting tech for Audi VW, not just Fat Bloke from the Red Lion who's good with motors

[m1bjr]

I know this is a 'man thing' okay - but why don't you read the leaflet that comes with the pads?

Different materials require different approaches.
I have installed a great many now, the various manufacturer's advice differs wildly.

Some high CoF 'race' pads require full-bore stops at high speed and then a long cooling period.
The manufacturers state this clearly in the accompanying leaflet.
In that particular case babying them will ruin them and possibly the discs too.

RTFM!

[doughboy]

Originally Posted by m1bjr

I know this is a 'man thing' okay - but why don't you read the leaflet that comes with the pads?

Beat me to it - pads are all different, read the leaflet!

IRCC yellow stuff have a highly abrasive top coating on which rapidly wears the disc to match the pad.

[bbillboyy]

Been doing abit of reading on a few different forums Audi/vauxhall etc alot of people are saying that pagid oem discs and yellowstuff pads are one of the best setups to go for and alot of people also are saying that yes they will squeal for a while.

When using my car this morning i noticed that the pedal is alot firmer and braking is alot better also the squealing has almost disappeared only when I really anchor on that it slightly squeals but general driving is fine now.

Because there a 'race' pad they probly will squeal a little when cold when they warm up they should be ok and alot sharper than normal just gotta find somewhere to get them up to temperature and test them out.

Cheers guys

[mob17]

Found EBC's recommendation:

In Street use situations …
Bedding in when the red EBC surface coating (marked on the pads as Brake In) is applied.
Best procedure is to drive gently avoiding harsh braking unless in an emergency for first 100 miles. In the second 100 miles (up to 200) you can use gently increasing brake pressures when using the brakes.
Only after 200 miles urban driving (not 200 miles on a freeway where brakes are almost unused) should you attempt to apply heavy load and heat to the brakes. To do this final bedding on a QUIET ROAD in safe traffic apply the brakes and slow from 60 to 10 MPH five times in a row. Then drive slowly for a few minutes if safe to do so to allow the brakes to cool. Try to avoid coming to a rest whilst the brakes are heated.
A smell may be noticed from the warm brakes, this is normal. Repeat this procedure a second time after the brakes have TOTALLY cooled down. EBC pads get better with miles. Even after this bed in procedure it can take up to 1500 miles before the pads are at their best. In the meantime the pads will be good and safe but true potential not realised. EBC makes performance pads that last, they do not bed in within 5 minutes driving. Noises will be more likely during the first 1000-1500 miles use whilst this chemical bedding takes place.