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Brake bleeding & maintenance...

Posted: Sat Sep 01, 2007 2:40 pm
by barnamania
Hi everyone,

I bought a zxr a while back and been working on it for a while... the brakes had all seized so I changed them. No problems on the back, but on the front I put some good brakes taken from a zzr600 which fit fine... I have bled the brakes for hours now, brake fluid is clear, the pistons are all moving in and out freely, BUT I can't build up any real pressure. Although the pistons move, they're not gripping the discs. I was guessing it's the brake assembly to blame, although it was working okish with the previous brakes (a few of the pistons hadn't seized).

Anyone have any ideas? Should I just keep pumping the brake to build up the pressure - I've been going for half an hour already? Cheers to all!

Re: Brake bleeding & maintenance...

Posted: Sat Sep 01, 2007 4:41 pm
by masterofinsanity
tie the lever back and leave it overnight with the top of the master cylinder, see how that goes, if still no pressure try changing the master cylinder.

Re: Brake bleeding & maintenance...

Posted: Sun Sep 02, 2007 4:03 pm
by barnamania
Thanks dude - tried that but no luck. Anyway... today I checked everything, had another hour long bleeding session. Im getting a nice fountain of sweet, clear brake fluid from the bleeding nipples, and I took off the hose that goes into the reservoir / pump - pressure from those is excellent. Must have got through a litre of brake fluid :smt013 Only thing I can think of is that the zxr reservoir is too small to handle the zzr600 brake calipers (pistons are larger). Could this be the problem? At the moment, I can push the brake all the way to the handlebar with almost no resistance, and the pistons make a slight movement, and they are touching the disc ok. Any more ideas anyone?

Re: Brake bleeding & maintenance...

Posted: Sun Sep 02, 2007 4:10 pm
by Northern ANdy
If the pistons are bigger then the force the fluid exerts on them will be greater but they will move less, as I'm sure you know. Have you tried bleeding the calipers off the disks, front brakes are always a pain in the behind. I turned my hoses on the master c round so they pointed up and hung up the calipers with the bleed nips at the top to try and get all the air out. Failing that get a zzr600 master cylinder.

Re: Brake bleeding & maintenance...

Posted: Sun Sep 02, 2007 7:21 pm
by barnamania
Thanks - yeah I did realise that, but I didn't know if a standard zxr400 master cylinder would have such a large effect or not. I have bled all the air out of the hoses - absolutely none left in there, but it's been a nightmare! Anyway... I'm going to get a new master cylinder as suggested, and maybe some braided hoses while I'm at it :smt007

Re: Brake bleeding & maintenance...

Posted: Sun Sep 02, 2007 8:58 pm
by barnamania
I've just won this - http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0145400172

Do you guys know if it's any good - and more importantly if it'll fit? Cheers!

Re: Brake bleeding & maintenance...

Posted: Sun Sep 02, 2007 9:35 pm
by Northern ANdy
well isn't that a nice lookin M/C. Looks like standard 7/8" dia clamp. Prob will fit I think.

Re: Brake bleeding & maintenance...

Posted: Mon Sep 03, 2007 4:58 pm
by barnamania
haha cool thanks

Re: Brake bleeding & maintenance...

Posted: Wed Sep 19, 2007 9:57 pm
by barnamania
hi again everyone... well the brembo didn't solve the problems. I'm now thinking it MUST be the new calipers I got (they were 2nd hand) - anyone have any calipers for sale?? :-)