Brake calipers

[dydey90]

Having some problems with doing up the brakes on my project ZZR600.
They were in a terrible condition when I got it, so I removed, stripped and replaced everything apart from the body of the caliper itself (pistons, seals, gaskets, bleed valves, pads, copper washers)

Stuck it back together and it's leaking.
Found one seal that I must have damaged fitting, so I ordered a new one and replaced it.

Still leaking

Any ideas?

Also, can't seem to bleed the rear brake, although that's all sealed fully so I'm probably just doing it wrong.
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This post is probably not serious and shouldn't be taken literally.
Past: CBR125,ER6f NINJA 650, ZZR600 Current: VFR750

[bladeblaster]

damaged it again?

Seals not seating properly?

[dydey90]

I checked, not damaged. All seem to be seated properly, I don't think there's room for them to not seat either.
____________________
This post is probably not serious and shouldn't be taken literally.
Past: CBR125,ER6f NINJA 650, ZZR600 Current: VFR750

[mudcow007]

sounds stupid this (an prob is) but i found i had used too much red grease to rebuild my calipers which was causing it to be a pain in the arse to bleed

stripped caliper again an cleaned most of it off an rebuilt an it was sweet.

dunno if that helps at all.....

[Beehive Bedlam]

You may have dislodged or twisted a seal as you pushed the piston back in. There's only one way to find out.

[dydey90]

[Stalk]

Had the same, New bleed nipples that were supplied with the kit where badly made and did not seat properly. Just leaked enough to make it hard to see through point of the leak, but could see the fluid dripping through the caliper.
Worth a look?
I put the old ones back in

[Fizzer Thou]

If you use some talcum powder where you think that the leak is coming from,then it will show up quicker.

If the leak is around the bleed nipples,as has been suggested a wrap or three of PTFE tape around the threads can help
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Just talk bikes.What else is there?

Always have a 'Plan B'

[Tdibs]

I have had the new bleed nipples with a rebuild kit leak before.
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Previous : 09 Vanvan 125| 02' Sv650s || Current: 1999 Xj600n | 1992 DR650 RSE | 2005 Fazer 1000

[Robby]

The back brake will be tricky if any point in the system is higher than either the bleed nipple or the master cylinder. Air will collect the highest point.

I tend to take the caliper off the bike - with the brake line attached, and a bit of wood between the pistons. Pump the brake until it firms up - expect to see bubbles in the reservoir. Finish off by opening the bleed nipple to let out the little pocket of air in the caliper.

Then refit to the bike, pump a bit more fluid out of the bleed nipple to make sure, and off I go.

[mentalboy]

[Carvel]

Did you split the calipers? The seals between the two halves are easy to lose/damage.

Is it obvious where it's coming from?
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2002 Aprilia RSV1000R, Cbr600Fs, Mk1 B12, Vfr400 NC30...

Matt B: I can deal with crushed nuts to beat Ollie.

[BanditsHigh]

Another potential is that you missed the little rubber washer out from between the caliper halves ... if you split the calipers that is.

Had a mate do this and also fit the wrong halves back together ... without the rubber washer between the halves it leaked like a sieve ... with the wrong halves together it only bled the one side!

You really need to eyeball the leak ... caliper off fork and a spanner between the pads/pistons ... pump lever and you should be able to spot it.

All the best ... Barry

[BanditsHigh]

[dydey90]

The seal kit included the little rubber washers, pretty sure they're in the right place. I'll double check.

I scraped out the buildup of crap in the recess and used a small wire brush to clean it up as best I could.

Also, because of the brass cover that goes over the locking pin that holds the pads in place, you can't assemble the wrong way round. The bolts that hold the cover in place are only present on one side. Left hand calliper doesn't appear to be leaking anyway.

I'll 'acquire' a roll of PTFE from work today and see if it is the bleed nipples.
I wonder if a spray of soap water would make it easier to pin-point the leak? I don't think there's enough fluid coming out for that to work.
____________________
This post is probably not serious and shouldn't be taken literally.
Past: CBR125,ER6f NINJA 650, ZZR600 Current: VFR750

[Vincent]

Any scratches on the pistons at all? They need to be as smooth as a babys bum
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Space Is Deep

[Rogerborg]

Are the seals square or is there any chamfering on them? If the latter, it's apparently[*] possible to put them in the wrong way around. There should be a distinct lip on the inside edge, when dragging a finger over them from the inside towards the outside of the pot.

https://youtu.be/EDfNb_9YkcI?t=770

[*] I say this, but I've yet to replace seals that weren't square. I can't speak to yours.
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Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[Raffles]

[smegballs]

[mentalboy]

[dydey90]

The bit where I made a mistake
____________________
This post is probably not serious and shouldn't be taken literally.
Past: CBR125,ER6f NINJA 650, ZZR600 Current: VFR750

[mentalboy]

[Rogerborg]

[DrSnoosnoo]