Brake callipers - splitting

[RiceBurner]

Just spoken with a Parts person at a BMW dealer, about TOKICO callipers on BMW bikes (the EVO system on R1150 series bikes).

I recently replaced the calliper seals on the callipers, by the usual method of splitting them, cleaning out and re-assembling. Since then I have been unable to bleed the system effectively (it's not ABS), and I'm normally pretty good at bleeding brakes.

BUT I have been told that splitting the callipers is a Bad Thing (tm) and the brakes will never seal properly again. (It should be added that BMW don't supply the calliper body seals so I had to re-use the originals.) Apparantly in order to replace the seals you have to grub around within the gap (which makes cleaning out the corroded seal chambers virtually impossible - or buy new callipers. )

Thing is - I did exactly the same job on my ZXR400 a few years ago - it wears Tokico callipers which are virtually identical to those on the BMW EVO system - and the job was utterly successful. (I was supplied the correctly calliper body seals that time, it should be added).

Has anyone else replaced the seals on the TOKICO BMW brakes, if so, how did you do it? Were you successful and did you split the callipers?

 

[Bronco Billy]

This looks like more than hitting things with a hammer so ...... over to you Steptoe ......

 

[Steptoe]

This looks like more than hitting things with a hammer so ...... over to you Steptoe ......

No need to split them to change the seals

 

[Voyager]

No need to split them to change the seals

OK . . .

But now that he has, what should he do next ?




Bob.

 

[Steptoe]

OK . . .

But now that he has, what should he do next ?




Bob.

How do i know- I didn't put them back together.
He said he's done it once with complete and utter success , so he's fully qualified

 

[Voyager]

 

[D6]

try puttin a long clear pipe on an LIGHTLY sucking on it as u blead them,DONT DRINK IT

 

[Noddy]

I'm sure that a few years back one of the manufacturers, Girling, Brembo stopped supplying caliper splitting overhaul kits. Came about cos some muppet did it wrong and they got the blame. They would only sell factory made calipers after. Sorry but I'm a bit

 

[DrFarkoff]

Refit them!

Bleed them!

See if you got away with it!

If ya didn't order 2 secondhand ones from the usual suspects

Simple as that

As a matter of interest where did you find the torque settings for the big bolts holding the jobbies together or are they now just "effin tight as"!"

You should never split the later calipers there's loadsa room to change pistons and callipers without that anyway ya just need yer Groove cleaning pick to see the job right

 

[rudiemoto]

these were bad,bandit 600

now with new seals and pistons clean there work ace,
my advice take it to someone who does as a job and knows there sh=t
its the brakes,there need to be spot on
and yes techs can fit seals 10 ways but me ,i always split them just the way i do it .and also you get all seals includes the little one that does body

 

[DrFarkoff]

Rudie I'm with You m8, Do the Job right and you only do the Job Once

BUT it's BM that say it's a No No to split the later Tokico / BMW callipers

Probably more to do with the pink micro encapsulated thread lock falling off into the body of the calliper but ya never know??/

 

[RiceBurner]

Refit them!

Bleed them!

See if you got away with it!

If ya didn't order 2 secondhand ones from the usual suspects

Simple as that

As a matter of interest where did you find the torque settings for the big bolts holding the jobbies together or are they now just "effin tight as"!"

You should never split the later calipers there's loadsa room to change pistons and callipers without that anyway ya just need yer Groove cleaning pick to see the job right

You mean re-split, check the body seals, then re-assemble??

They're only "effin tight" unfortunately. IIRC I didn't use a torque wrench on the aforementioned ZXR Tokicos either.

Do you mean 2x 2nd hand callipers?? hmmm I hope it doesn't come to that.

The main reason for splitting the callipers was to get the pistons out - I don't have a compressor so have to use the fluid pressure to get the pistons most of the way out, then wiggle them out the rest of the way (I had to take the old pistons out with mole grips. ) The only wa I can see to do it without splitting the calliper is to use fluid pressure to push out each piston in turn and clean each bore in turn - but then you'd get shit loads of crap caught in the calliper innards wouldn't you?? I can't see any other way to do it.


On other thing: When bleeding, if I loosen the nipple to the minimum amount to allow the pressure to release, when I re-tighten the nipple I can feel the increase in pressure at the lever from the nipple body re-entering the calliper - surely that means the system is tight, if I can feel that minute increase???

 

[RiceBurner]

these were bad,bandit 600

now with new seals and pistons clean there work ace,
my advice take it to someone who does as a job and knows there sh=t
its the brakes,there need to be spot on
and yes techs can fit seals 10 ways but me ,i always split them just the way i do it .and also you get all seals includes the little one that does body

Ah - sliding callipers - yeah they're easy, did some on a Zephyr not long ago, p.o.p. to get at everything.

 

[RiceBurner]

How do i know- I didn't put them back together.
He said he's done it once with complete and utter success , so he's fully qualified

I'm flattered...

(I think).

 

[Steptoe]

[
now with new seals and pistons clean there work ace,
my advice take it to someone who does as a job and knows there sh=t
its the brakes,there need to be spot on
and yes techs can fit seals 10 ways but me ,i always split them just the way i do it .and also you get all seals includes the little one that does body

Ah - sliding callipers - yeah they're easy, did some on a Zephyr not long ago, p.o.p. to get at everything.

yes, as riceburner says - sliding calipers. No need to split those, they slide apart Hence the name, "sliding" calipers

 

[DrFarkoff]

You mean re-split, check the body seals, then re-assemble??

They're only "effin tight" unfortunately. IIRC I didn't use a torque wrench on the aforementioned ZXR Tokicos either.

Do you mean 2x 2nd hand callipers?? hmmm I hope it doesn't come to that.

HI Riceburner don't sweat it too much if you were sure it all went together clean and they aren't leaking at the split face then you may have got away with it

I prefer the hassle of wiggling the feckers to get em out that wee bit rather than risking a calliper by splitting them!
Besides a bloody good clean down with a toothbrush and ACF50 (not on brakepads Just in case there's a numpty on the loose) and a wiggle in an out starts things movin easier all round if ya haven't got acf use a teaspoon of clean brakefluid

 

[RiceBurner]

HI Riceburner don't sweat it too much if you were sure it all went together clean and they aren't leaking at the split face then you may have got away with it

I'm hoping so. After the 1st night I had the lever tied back to the bar I noticed a slight weep at the M/c - so tightened that up - no leaks whatsoever since that I can see. (I tied the lever back overnight a further 3 times).

I prefer the hassle of wiggling the feckers to get em out that wee bit rather than risking a calliper by splitting them!
Besides a bloody good clean down with a toothbrush and ACF50 (not on brakepads Just in case there's a numpty on the loose) and a wiggle in an out starts things movin easier all round if ya haven't got acf use a teaspoon of clean brakefluid

Good tip - will try to remember that next time.

 

[rudiemoto]

i was just showing how bad brakes r,
i will post some pics from works pc it has 2000 pics of brakes,and service work and p8rn

 

[RiceBurner]

i was just showing how bad brakes r,
i will post some pics from works pc it has 2000 pics of brakes,and service work and p8rn

Just stick to the p8rn mate - it's probably cleaner.

 

[RiceBurner]

For those who may be interested....

After re-fitting the calipers, and fitting the 2nd hand master cylinder (one of the reservoir threads had gone), then fitting full braided hoses, bleeding with a MityVac, refitting the original m/c, bleeding, re-fitting 2nd hand m/c,.... I finally succumbed and bought a 2nd hand set of calipers from Motorworks.

Luckily they turned up the day before the MOT was booked and I was able to fit them and regain brakes worthy of the name!

I think I didn't get away with using those old caliper body seals.

So - lesson learnt - replace ALL the seals, and don't be so sure that you know what you're doing...