FOAK - stuck caliper piston

Around 20-year old Brembo, so I should perhaps have queried in ukrmc.

Anyhow, I now have the caliper off the rear wheel; one piston would not
return back into the caliper. After applying some force I managed to
press it back in, and after some further pressing in/out, it can now be
moved in (fully) and out fairly easily.

Will it rapidly seize again if I just put the caliper back on, soon
requiring another strip? I.e. is further cleaning of the piston
(including caliper splitting) recommended, now that I have the caliper
off already?

Thanks for constructive suggestions!

 

muck@_TEETH_rulex.net (Muck) wrote in message

Motorworks sell a complete set of seals and also slider pins and all the
rest of the gubbins. The pistons are ceramic as well so they don't rust
in the way that chromed ones do.

If it were mine I'd strip it and clean it properly. Actually, when I
stop and think about it that's exactly what I did to my 20+ year old
K100. Not really a difficult job.

 

It's definitely worth doing the whole job... they will seize up again
soon if you don't, and your brake's will work properly if you do.
You don't need new seal's either [unless they're badly damaged], just
be careful and clean the seal's with a stanley knife blade to scrape
the corrosion off. The easiest way to get the corrosion out of the seal
seat, is to bend a small electrical screw driver to just over 90
degree's and scrape it out with that, being careful not to damage the
surface in the process... clean the rest as you see fit.
Keep your brake's in good condition at all time's, is my advice.
Hope ive helped a bit.
Mick.

 

It's definitely worth doing the whole job... they will seize up again
soon if you don't, and your brake's will work properly if you do.
You don't need new seal's either [unless they're badly damaged], just
be careful and clean the seal's with a stanley knife blade to scrape
the corrosion off. The easiest way to get the corrosion out of the seal
seat, is to bend a small electrical screw driver to just over "90
degree's" and scrape it out with that, being careful not to damage the
surface in the process... clean the rest as you see fit.
Keep your brake's in good condition at all time's, is my advice.
Hope ive helped a bit.
Mick.

 

Are you sure about this? We're talking about a twenty year old bike.

 

Thanks for all comments. When reading my OP it may seem like I would
skip the rebuild completely - that was not my intention!

I should have specified that the options were:

a) put it together now, ride[1] the rest of the summer (no salt on
roads), hopefully without problems. Strip and rebuild all three
calipers[2] sometime during winter when the bike is not used much, and
when I have more time to order and wait for spare parts to arrive.

b) complete split and rebuild now[3], which means I cannot ride the bike
for anotherr week.

[1] only leisure, I do not commute on it
[2] if one has seized, all have been at risk and may follow suit if not
restored
[3] since the caliper _will_ seize again in two weeks time

 

(ts) wrote in message

Why don't you just buy the caliper rebuild kits and rebuild when they
arrive?

It took me about 3-4 hours to rebuild the three calipers on my K100
including taking them off the bike, cleaning, putting them back on the
bike bleeding etc. etc.

 

1. It is only a back brake.
2. It will probably be fine for the rest of Summer.
3. Get the parts before undertaking dismantling.
4. Make sure you have the correct parts before undertaking
dismantling.
5. Think about how long it has been since your last brake service -
therefore how long it has taken to seize in the first place.

Not an issue then, is it?

Equally bollocks.

Get on it and ride it - remember to use the rear brake a good bit,
then it will be less likely to seize. Sort it properly in Winter.

 

(snip)

That was actually what I hoped to hear

 

(snip)

You obviously have more practice than I. My approach to bike servicing
has ended up rather spending a bit more time figuring out how to take
things apart without destroying other bits of the bike in the process.

And figuring out how to do things in a practical way, instead of
following the step-by-step instructions in the BoLs. Like how to avoid
depressurising the fuel system and taking off the tank to get access to
the air filter, as Clymer suggests. I would probably need a week-end to
rebuild 3 calipers, on and off, doing other things at the same time.

 

Ive stripped and cleaned endless amounts of old and new brakes and
bought a set of seals once ['70's GS 550 i think]!
I ride a 1978 Z 650 and a 1989 FZR 600 and do all my own work...
Ofcourse im sure else i wouldnt have put it on here...

 

Unhinged says...

I sure as hell wouldn't trust a set of seals that old. They can perish
and they can shrink and also swell over time. If you're going to have
the brakes apart you may as well put new seals in and know the job is
done properly.

In all fairness, a 1978 Z650 and a 1989 FZR600 aren't in the same league
as a ZX-6R in the braking stakes to start with, so you probably wouldn't
notice a drop in performance like you do when a Tokico starts to play
up. The Tokico 6 pots fitted to the ZX are notorious for requiring a
full rebuild often or the braking performance drops dramatically. A full
rebuild in my opinion is a set of seals as well. If you remove them,
replace them with new ones.

A tip for the OP. Don't buy genuine Kawasaki seals, source them from
your Suzuki dealer. Some Suzukis, such as the Hyabusa and TL1000R, used
the same style of 6 pot Tokico calipers and the Suzuki seals are half
the price of Kawasaki ones. Just make sure you get the right size seals
as some Kawasakis, such as the ZX-7R, have two sizes of piston in each
caliper. All the Suzukis I've seen have all 6 pistons the same size as
the Kawasaki's larger ones, but this may not be the case with all
Tokicos.

 

You sir, are a dangerous ****.