Brembo front calipers

[Grim Rider]

I have searched and searched for an answer to this question so apologies if the answer is out there - I am considering replacing the seals and pistons in the front calipers of my 2001 GS (Brembo calipers, ABS non servo) because they seem pretty mucky and stiff after 13 years and 100k. I can find lots of reference to splitting the later BMW Tokico calipers but not about whether you can replace the pistons in those fitted to mine without splitting them, and if so the best way to go about it? Thanks for your replies.

 

[crispy duck]

U could try pull them out and replace the seals and piston but why not just split them ? I'm not 100% sure on your exact caliper but I doubt it's going to be hard to do. U might be able to just clean up the pistons with new seals

Sent from my HTC One using Tapatalk

 

[GARAGE HERMIT X2]

if they're not leaking, your piston's and seal's are ok, take them off the bike, remove the pad's and give the caliper's a good clean,

 

[DrFarkoff]

I was doing a pair of Bembo last night but I think yours are the older ones with Brembo written on the outside with silver circles around it? You can change pistons and seals in these models without splitting them easier than the later callipers

Its pretty much the same scenario BUT take note!! if the 4 small bolts won't move don't force them!!!!

Turn the calliper over you will see sections of the bolts are exposed underneath and there is likely to be salt ingress either side and into the threads and the through passage

The only really successful way I've found when the bolts are jammed is to cable tie the calliper upside down to a bit of wood so you can keep your feet back while you stand on the wood to steam clean them to dissolve as much of the rust and salt crystallization as possible

If you are not going to split them

My only tip is to Block the pistons that do move easily and get the stuck one or ones out a bit so you can grip them with water pump pliers to rotate them out (Like I said easier in the old Brembo callipers than later ones)

Be careful, if you are just going to remove the piston and clean out the wiper ring groove of salt the centre bit of each piston is a bit of hard plastic and it can break but its not the end of the world

You can see the salt and grime on the one above

Its good to get to the end after cleaning off all that yeugh and have a nice free moving calliper again!

 

[monkeyboy]

Ditto that - I did mine on my 2000 R1100S with the same calipers as yours. No need to split. Just carefully clean out the seal recesses when they're appart cos a mixture of corrosion and muck will be in there for sure. Straight forward job - just hate bleeding the buggers after.

 

[The Grey One]

I was doing a pair of Bembo last night but I think yours are the older ones with Brembo written on the outside with silver circles around it? You can change pistons and seals in these models without splitting them easier than the later callipers

Its pretty much the same scenario BUT take note!! if the 4 small bolts won't move don't force them!!!!

Turn the calliper over you will see sections of the bolts are exposed underneath and there is likely to be salt ingress either side and into the threads and the through passage

The only really successful way I've found when the bolts are jammed is to cable tie the calliper upside down to a bit of wood so you can keep your feet back while you stand on the wood to steam clean them to dissolve as much of the rust and salt crystallization as possible

If you are not going to split them

My only tip is to Block the pistons that do move easily and get the stuck one or ones out a bit so you can grip them with water pump pliers to rotate them out

Careful the centre bit of each piston is a bit of hard plastic and it can break but its not the end of the world

Using water pump pliers, or anything like that, is a sure way to knacker the pistons. Only do that if you have new pistons at hand to fit. Compressed air via the bleed nipple works, I have got a few out just by using a foot pump. Another method is to use a grease gun attached to the bleed nipple but you do need to be able to clean out the calliper afterwards.

John

 

[GARAGE HERMIT X2]

i split the caliper's then use mole-grip's with a thin strip of alloy bent into a U shape to cover the m/g jaw's, worked fine for me, i've the caliper's with the circle's on them,

 

[DrFarkoff]

Good for the heads up John I was kinda knackered this morning

But thats why I said block the other pistons that do move and pump out the stuck one

I did however omit to say by only gripping the outer 3 or 4 mm you are outside the wiper ring area and this part of the piston is likely to be corroded and damaged and it won't make a difference unless you are REALLY cack handed

Using water pump pliers, or anything like that, is a sure way to knacker the pistons

 

[Grim Rider]

Thanks for the really helpful replies - mine are the older type with Brembo and circles on the outside. Have new seals and pistons ready as I managed to mangle the piston on my Bonneville last time I did the same job (mind you, that looked more corroded after 3 years than the BM ones do after 13!). Job all set for the weekend, cheers!