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actungbaby
3rd April 2012, 20:00
Hi i recently dismantled my vfr 750 brake calibers i got my nephew to take brakes into mechical course

tutor told him to get new cailbers cause mine where junk seized surly there way to get pistons out

I tryed CRC brake cleaner tooth brush (seemed waste time) was thinking scouring pad to get crud of around pistons

Also though heat (hot air gun) not tryed yet .i got 2 calbers one has bent arm , so even I get one side working

if its possible to give me one working side left side brakes , if i sacrfice one caliber to get one working one thats okay .

it possible to get you fingers or tool in to push remaining one out , if you get one out even if you have to damage it with pliers

And just any ideas whould be great help i never had this problem b4 .

I purchased kit to make sure master Cylinder is all good know but dont want cause damage to new seals if the pistons are stuck.

Are they designed to pull out and have seals replaced or do you buy at the least new pistons look bit expensive as

There like brass coated , was also going to spray cleaner in trough where brake fulid goes and sit them so


All in all with one rotor replaced and found the other to be warped ,this brake system been pain in the rear to say the least

DrunkenMistake
3rd April 2012, 20:13
Found it a little hard to make heads or tails of your thread but basicly your asking if there is an easier way to remove the pistons?

If so..

You can use compressed air to blow through where the bleed nipple screws in, I know you can push them out while they are assembled by removing your brake pads so they push out.

dogsnbikes
3rd April 2012, 20:22
Had same problem with the CBR last year,Yes you can use compressed air but be careful if they are stuck when they let go you can spend days looking for a piston:facepalm:.....I had a ceramic piston in the antidive caliper which needed too be repleced and discovered it was a deleted item so I got a stainless one turned up at a local engineering shop for around $40 dollars

FJRider
3rd April 2012, 21:00
You can use compressed air to blow through where the bleed nipple screws in, I know you can push them out while they are assembled by removing your brake pads so they push out.

A threaded plug on the inlet side with a grease nipple can sometimes move it.

actungbaby
3rd April 2012, 21:02
Found it a little hard to make heads or tails of your thread but basicly your asking if there is an easier way to remove the pistons?

If so..

You can use compressed air to blow through where the bleed nipple screws in, I know you can push them out while they are assembled by removing your brake pads so they push out.

yeah he tryed compressed air behind the pistons that didint work i mean these things just dont move i tryed a bit wood and hammer

actungbaby
3rd April 2012, 21:05
Had same problem with the CBR last year,Yes you can use compressed air but be careful if they are stuck when they let go you can spend days looking for a piston:facepalm:.....I had a ceramic piston in the antidive caliper which needed too be repleced and discovered it was a deleted item so I got a stainless one turned up at a local engineering shop for around $40 dollars

thats good idea thanks for that do you think in the bleed line whould work better than what we tryed just air in trough
where main hose drive the fuild in , if so we try that tommrow

ducatilover
3rd April 2012, 21:18
Measure the bolt spacing for them mate.
I'm off to google, I have a plan.
If compressed air didn't work, put them back on and try bleed 'em, you may be able to push the pistons out a little.

Asher
3rd April 2012, 21:27
You could connect them back up and pull them on without pads and they will come most of the way out

jellywrestler
3rd April 2012, 21:29
a lot of calipers have a fine thread metric bolt holding the lines on, the same thread form as a lot of grease gun fittings , simply thread in the grease gun and work the gun.
rare that it doesn't work and way way more successful than compressed air

actungbaby
3rd April 2012, 21:36
Thanks mate your diamond in the rough

Am just about pulling my hair out here with frustraion and dam scary riding with no fron binders

dam nutas in cars trying kiill me had guy van do good move on me by the bridge

Got offer on 95 vfr 750 calibers on ebay but sure they use floating dsics mine dont

heres a picture even drop them of to you there no good here , i was worried if hooked up line

I blow my seals in my master cylinder if they didnt move but i havent tryed that yet.
opps put pic of my boss sleeping in bed sorry he also my chief mechanic and future motogp star



Measure the bolt spacing for them mate.
I'm off to google, I have a plan.
If compressed air didn't work, put them back on and try bleed 'em, you may be able to push the pistons out a little.

ducatilover
3rd April 2012, 21:38
a lot of calipers have a fine thread metric bolt holding the lines on, the same thread form as a lot of grease gun fittings , simply thread in the grease gun and work the gun.
rare that it doesn't work and way way more successful than compressed air

Great to know, thanks!

actungbaby
3rd April 2012, 21:44
You could connect them back up and pull them on without pads and they will come most of the way out

thanks mate was bit of a woss i went fixed my front guard and welded it toghter with solidering iron and its working sometimes going for does work

actungbaby
3rd April 2012, 21:48
yes thanks great advice at this stage i put my bike pump on there if it work as thats only thing i got

8 1/2 cm from bolt hole to bolt hole on the fork legs


Great to know, thanks!

ducatilover
3rd April 2012, 21:49
Hmm I thought they had the 4 pot ones on 'em.
If you buy VTR100 lowers you could upgrade to Nissin 4 pot brakes, my spare Tokico ones will bolt to VTR forks.

If you can gett he measurement between the bolt holes on the calliper where it mounts to the factory adapter plate, that'd help.
I'll try find some more info and see if we can put my spare ones on it.

ducatilover
3rd April 2012, 21:57
Research says:
VTR1000 fork lowers.
I know for a fact if you do this, you can fit CBR600F4 gold four pots (and VTR ones, same caliper), GSX-R1000 6 piston calipers bolt straight on and my ZZR ones can be made to fit, along with several others.

actungbaby
3rd April 2012, 22:02
Research says:
VTR1000 fork lowers.
I know for a fact if you do this, you can fit CBR600F4 gold four pots (and VTR ones, same caliper), GSX-R1000 6 piston calipers bolt straight on and my ZZR ones can be made to fit, along with several others.

my rotors arent floating ones there soilid so calibers move where ones you mentioned say the brakes be soild

and the discs have washers that float to stop warping very cool . like race bike cool only years ago

where as my right disc is bloody warped as hell aghhhh its like good 10mm in parts u can see it let alone measure it

my god no wonder dude locked up his brakes the right disc was warped to hell and pistons where seized

I have read where vtr forks do fit in to vfr 750 there like 5mm diffrence but as your aloowed to sit tops the forks above the clip ons

I must try this to sharpen sterring , when you going take ride on the bike dude ? you welcome too

ducatilover
3rd April 2012, 22:09
The VFR fork lowers will go on, might be worth finding some and throwing new seals in.
Then get some new disks from somewhere lol

I'm in Eketahuna for a wee bit with no transport (sold my car today) but I certainly have to ride it

HenryDorsetCase
3rd April 2012, 22:09
a lot of calipers have a fine thread metric bolt holding the lines on, the same thread form as a lot of grease gun fittings , simply thread in the grease gun and work the gun.
rare that it doesn't work and way way more successful than compressed air

Today I learned.........


excellent tip, cheers!

stuck pistons are a bitch.

that red grease and new seals and CLEAN them really well and they'll work like a charm. I couldnt believe the difference it made to my VFR400 when I did it.

actungbaby
5th April 2012, 10:06
Today I learned.........


excellent tip, cheers!

stuck pistons are a bitch.

that red grease and new seals and CLEAN them really well and they'll work like a charm. I couldnt believe the difference it made to my VFR400 when I did it.

Great mate good to here i got one piston you , what rubber grease did you us on your seals i need to buy some
Guy at city honda (top guy) said to use some , in fact nice people at city honda