Disc and pad change

[ethan]

Done the above:first time. Is it common for breaking to be initially soft until the new pads etc have had time to bed themselves in? Thank you.

 

[classicVin]

you can brake as hard as you want, just do not get them to hot ! As the discs can get so hot they will start to warp.

 

[Janesy B]

How do you mean soft? The pads will take a while to bed in, the first time I drove with brand new pads it felt like I had no brakes at all! Does the pedal feel soft?

 

[Cybermyk]

I used to always bed new discs and pads in on bikes by braking fairly hard from 70 down to 10-20 keeping moving, then accelerate and do it again. Only ever replaced a full set on a car once but it seemed OK from the first use.

 

[Janesy B]

Seems a little unusual to be braking hard on brand new pads? I just braked gently on my normal journey to work and they were bedded in nicely.

 

[InvaderGIR]

Seems a little usually to be braking hard on brand new pads? I just braked gently on my normal journey to work and they were bedded in nicely.

Ideally you need to bed them in gently, not harshly.

Also you may need to bleed the brake lines as you could have gotten air in the system, which if the pedal is really soft could be explained by this.

 

[Janesy B]

I meant to put unusual, not usually :s

Seems a bit daft to slam the brakes on with brand new pads.

 

[InvaderGIR]

I meant to put unusual, not usually :s

Seems a bit daft to slam the brakes on with brand new pads.

I knew what you meant, was agreeing with you.

It is daft to slam the brakes on with new discs and pads.

 

[rG-tom]

it's a hard one

discs like being worn in slowly, pads like being worn in quickly, so you've got to compromise

 

[InvaderGIR]

If replacing both the safe bet is to bed them in gently.

 

[Berger]

I fitted new discs and pads on Thursday to my car.

First application of the brakes at the end of my street they were a little soft.

Went and bedded them in by doing 60mph - 20mph fairly hard about 15 times, the key point being not stopping. They stank after about 3 stops but the smell went and they got better, after this went up the motorway and gave them about 15 minutes with no / light use to cool the discs down.

Will depend on the pads/discs used as how harsh you want to be with them, I fitted Ferodo DS2500s and Brembo discs which is a more track orientated combo so I wasnt too worried about the pads. Whats recommended by the manufacturer inside the box they came in?

 

[Fido McNasty]

Just try to be progressive in application for the first 50 miles or so. There's little more to it than that.

 

[ethan]

How do you mean soft? The pads will take a while to bed in, the first time I drove with brand new pads it felt like I had no brakes at all! Does the pedal feel soft?

I think you have summarised it quite well

 

[Slime101]

If the pedal is soft then bleed the brakes, you may also need to bleed the master cylinder and be aware cars like audis and vw's have twin bleed nipples on the master cylinder which are a real pain to get at!

 

[Lopéz]

Yes, the pedal will often feel a little spongy at first. It should not need bleeding after a pad change.

 

[numnutz]

Ideally you need to bed them in gently, not harshly.

Also you may need to bleed the brake lines as you could have gotten air in the system, which if the pedal is really soft could be explained by this.

Ideally you'll bed them in as per instructions. Most 'fast road' pads work a lot better when bedded in via 70mph - 20mph repeated multiple times. The important bit is not to come to a stop and let the pad sit on the disc in one place.

 

[InvaderGIR]

He did both pads and discs, and I was summarising what others had said, discs slowly, pads slightly harsher, so you have to compromise.

 

[ethos]

To quote Nick Adams (Lotus development engineer)

With new pads and discs, or just new pads fitted run the car around for 10/20 miles using the brakes gently as normal to bed the two surfaces together. Once this has been done, check the surfaces of the discs and make sure there are no signs of any scoring or damage. Assuming all looks well take the car to an appropriate piece of quiet and straight, well sighted road and perform half a dozen medium pressure stops from 50 mph down to 20 mph to warm the brakes up. Avoid more than a minute between each stop so that the temperatures do not get a chance to deteriorate too much. Once the brakes are warm and the coast is clear, perform 2 or 3 hard stops from 70mph (where local laws allow!) to 20 mph, braking as hard as you can without locking up. Do not come to a halt between each stop, do them as fast as you can to get the brakes really hot. On the third stop come to a halt and, keeping your foot on the brake, press the brake pedal down as hard as you can and hold it there for at least a couple of minutes, don't apply the handbrake. This hurts if you are doing it right! This will bed the pistons, shims and pads together and will compress the pad material, giving a hard and repeatable pedal. Once the 2 minutes have passed, release the pedal and go for a short drive, using the brakes as normal to let everything return to normal temperatures. The brakes are now fully bedded in and ready for use in anger. Recompressing the pads once every few thousand miles to the above procedure will help keep the pedal firm, especially if you don't normally use the brakes hard.