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Posted: Mon Apr 14, 2008 2:52 pm
by RiceBurner
throttlemeister wrote:Mine were stuck to the point I could not move them by hand. They were blown out before I had full pressure on. They blow out really easy with air.
I can't move them by hand when the seals are perfectly new!
Posted: Mon Apr 14, 2008 3:00 pm
by Phil K
I had to find thicker o-rings, as the ones supplied in the kits were visibly thinner than the ones that came out.
Archie, I hope that you checked on the material!
****For use in brake fluid you should use EPDM not standard Nitrile *****
Nitrile will fail very soon after fitting - not good at speed
Phil
Posted: Mon Apr 14, 2008 4:03 pm
by Archie
Yes, I went to an industrial seal supplier who sorted me out.
Just an aside...
Posted: Mon Apr 14, 2008 4:19 pm
by snavetrauts
I had some stuck pistons recently on my R100RS.... would not budge..so used air.... unfortunately my finger was in the way at the time... bloody painful.
I have split brembo's many times with no problems... on one occasion, using the original o rings again.... again no problems.
Good luck.
Stuart
Posted: Tue Apr 15, 2008 12:24 pm
by RiceBurner
Phil K wrote:I had to find thicker o-rings, as the ones supplied in the kits were visibly thinner than the ones that came out.
Archie, I hope that you checked on the material!
****For use in brake fluid you should use EPDM not standard Nitrile *****
Nitrile will fail very soon after fitting - not good at speed
Phil
Precisely why I stuck m old ones back in instead of trying a random set from the "B&Q bumper box of o-rings" I have in the garage.... I have no idea what material they are!
Just waiting for my new Goodridge lines to turn up from brakes4u.com.

Posted: Tue Apr 15, 2008 9:47 pm
by Yogi Bear
Posted: Tue Apr 15, 2008 10:24 pm
by Boxered
You should be a detective Ali
Steve
Posted: Wed Apr 16, 2008 5:03 am
by throttlemeister
Blackal wrote:throttlemeister wrote:Mine were stuck to the point I could not move them by hand. They were blown out before I had full pressure on. They blow out really easy with air.
Why not just couple them back up to the brake master cylinder and use hydraulic pressure to shift them?
Hydraulic power is a lot safer than coupling up an air hose.
Using compressed air is a bit "Yee-Hah" in comparison
Al

Cause once you got the first two out, how do you expect the next two to come out without fluid in there?
It's not that YeeHaw, but you need to be careful. You just put the airgun into the where the banjo bolt goes, and give it a _little_ air and out they come.
It is actually the only way to get them out easily and done like that in every shop. It is also explicitly mentioned in the Hayes manual to do it like this.
Posted: Wed Apr 16, 2008 10:13 am
by RiceBurner
throttlemeister wrote:Blackal wrote:throttlemeister wrote:Mine were stuck to the point I could not move them by hand. They were blown out before I had full pressure on. They blow out really easy with air.
Why not just couple them back up to the brake master cylinder and use hydraulic pressure to shift them?
Hydraulic power is a lot safer than coupling up an air hose.
Using compressed air is a bit "Yee-Hah" in comparison
Al

Cause once you got the first two out, how do you expect the next two to come out without fluid in there?
It's not that YeeHaw, but you need to be careful. You just put the airgun into the where the banjo bolt goes, and give it a _little_ air and out they come.
It is actually the only way to get them out easily and done like that in every shop. It is also explicitly mentioned in the Hayes manual to do it like this.
How do you plug the hole once the first one comes out?
Posted: Wed Apr 16, 2008 11:23 am
by scotty
Archie / Phil K
Where can I get the right size seals that seal the two halfs of the Brembo calipers ? Was going to use B&Q jobs but a bit worried after Phils post
Regards
Posted: Wed Apr 16, 2008 12:59 pm
by julian
On a previous S, I made a wooden block with a piston sized notch which allowed only one piston to operate at any given time (but not far enough to pop it out) using the brake lever. Remove the block, clean the piston surface and then push back in. Repeat on other pistons.
My current pistons work back in with resonable finger pressure but after each 6 months' use (4k miles) some are more sticky than others .
Posted: Thu Apr 17, 2008 5:51 pm
by Blackal
julian wrote:On a previous S, I made a wooden block with a piston sized notch which allowed only one piston to operate at any given time (but not far enough to pop it out) using the brake lever. Remove the block, clean the piston surface and then push back in. Repeat on other pistons.
My current pistons work back in with resonable finger pressure but after each 6 months' use (4k miles) some are more sticky than others .
Yeah - that would do it. I would certainly try to do it with hydraulics - too many workshop accidents attributed to inappropriate use of compressed air.
Al

Posted: Mon Apr 21, 2008 11:41 pm
by jivebiker
If you loosen all the pistons up and thoroughly clean externally before popping any out, then the others should pop out more easily even with a bit of air in the system.
I have yet to find a piston so stuck that hydraulic brake pressure cant get it moving, but check that piston to body clearance on the trailing edge, mine was well corroded and jamming against the piston. All nice and free now though.