Brembo Callipers

M

Mirage80

New member
Location
Surrey
Having just had both my PS15 calliper’s refurbished (great job by Powehouse) and recharging the system, I have correctly bled the outside pistons. However I can’t seem to bleed the inner pistons, is there a technique I’m missing as it almost seems like there’s no flow of brake fluid into these?
Thanks.
 
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Are they single nipple ? I guess you mean P08 ? If so take them off the forks and tilt them to get the trapped air up to the nipple.

How much do power house charge ?
 
Paddy said:
Are they single nipple ? I guess you mean P08 ? If so take them off the forks and tilt them to get the trapped air up to the nipple.

How much do power house charge ?
Click to expand...
They have two nipples on each calliper. I believe they are PS15s.
I’ve tried tipping them every which way but loose.
Powerhouse charged around £130
 
I recall a tip from here was to push the pistons back as far as they’d go a couple of times, there’s a lot of fluid that seems to miss getting bled normally. I certainly removed a lot of bad juju. Although mine are just the P08s, single nipple.
 
£130 !! Blimey, should have come to me :) PS15 is a master cylinder.
What makes you think your P08 calipers are only bleeding one side ? For example how do you know ? have you got any feel on the lever ? have you tried tying the lever back ? Have you had the master cylinder apart ?
 
I'm pretty sure PS15 refers to the master cylinder.
Calipers are P2F08, but I'm likely to get into trouble for being pedantic by giving its complete name. Most people just refer to them as P08.
I dunno whether the single nipple and double nipple versions have different designations. Perhaps just different part numbers.

I find a vacuum bleeder works quite well but the process will be helped by Paddy and Andy's suggestions.
Hold the nipple upright because that's where the air bubbles go.
Pressing the piston in as far as it'll go reduces the volume to be bled and helps push any bubbles out.

But sometimes a bit of air in the system is a not such a bad thing.

I bled the brakes on my Moto Guzzi LM1 the other day. It has the famous (or infamous) Guzzi linked system in which one front disk is operated by the rear brake system, and the other front disk is operated by the hand lever. Some people love the system, others hate it. I prefer the separate front and back brakes but can live with the linked system. I can see the advantages of doing it that way on a road bike.

The rear brake system bled OK, then I turned my attention to the front brake, which needed a new hydraulic brake light switch.

The front brake lever has always felt very wooden, with almost no movement in the lever when the pressure comes on. I've assumed that's because it uses a PS15 master cylinder, which is a good size when it's operating 2 calipers, but over-sized when it's operating only one. While replacing the buggered brake light switch on the front master cylinder, a bit of air inevitably got into the system (probably an air cavity in the switch itself). I was about to bleed it out but discovered that it actually feels better with air in there. The lever has a little more travel and the brake feels much more progressive!
 
Paddy said:
£130 !! Blimey, should have come to me :) PS15 is a master cylinder.
What makes you think your P08 calipers are only bleeding one side ? For example how do you know ? have you got any feel on the lever ? have you tried tying the lever back ? Have you had the master cylinder apart ?
Click to expand...
I have attached a clear drain tube to each nipple in turn and unscrewed the nipple whilst pumping the brake lever, each of the outer piston chambers fill the tube but using the same process nothing comes out of the inner piston nipples. I’m doing this one at a time with the calliper in place so the method is the same.
I think I might try compressing and clamping the working piston In with the calliper off the disc to see if I can “free” the inner piston by pumping the lever.
 
Might not be a solution to your specific problem. But I always remove the splitter from the triple clamp
while bleeding the brakes.
So I can tilt it in different directions, as sometimes air got caught in it.

Ernesto
 
When I rework/overhaul calipers, I put the pistons in just so they do not fall out, fill the caliper with brake fluid, connect them to the system, fill the system (but the reservoir just 2 mm high to avoid overflows with the following step) and slowly press the pistons in while making sure, the brake line connecting point is the highest point of the caliper. That normally pumps the air out 99,9%. The rest is a question of slowly pumping the brake master at the point where the bubbles come up. If you have a resistance point where you can build up pressure, mount the calipers properly, pump the master and tie it down with some straps/rubber straps etc. so it holds the pressure. Air will come up in the lines over night...
I even exchanged Calipers on cars without the need to air-bleed the system afterwards. Works well... ;-)
 
I think i might know what going on here.
they have assembled these back to front. The rear of each caliper is handed and must match up with its original front.

If you want to send them to me i will check them over FOC and sort them out.
For £130 each i would have supplied new pistons seals, had them cerakoted with new pins and nipples pads etc.

Reconditioning

Reconditioning
www.ducatipaddy.com www.ducatipaddy.com
 
Paddy said:
I think i might know what going on here.
they have assembled these back to front. The rear of each caliper is handed and must match up with its original front.

If you want to send them to me i will check them over FOC and sort them out.
For £130 each i would have supplied new pistons seals, had them cerakoted with new pins and nipples pads etc.

Reconditioning

Reconditioning
www.ducatipaddy.com www.ducatipaddy.com
Click to expand...
Hi Paddy
Thanks for your offer I can contact you separately from here.
 
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