Tools needed in addition to bike toolkit
Dot4 compatible clutch and brake fluid
Compressed air (this is a 100% necessary. If you haven't got it, don't even attempt this. you will not get the pistons out of the bores if they are remotely
tight.. unless you want to wreck them)
Bleeding kit of choice
6mm Allen key (with good purchase ability)
Long nose pliers
Clean lint free rag
Can of aerosol brake and clutch cleaner
circlip pliers (straight, squeeze to open)
GETTING TO THE PROBLEM
Remove the front brake master cylinder cover, and 2 part diaphragm.
start on RH Side. using 6mm Allen key, break the seal on the 4 cap head bolts on the calipers. (just so you hear them crack, then stop)
Remove anti squeal spring, R clip and pad holding pin.
Gently depressing the front brake lever, look inside to see which pistons are moving and which appear
seized. put the brake pad in sideways to hold the moving ones, while still allowing the
seized ones to move (top ones will more than likely be seized. bottom and middle, not) remember to hold both sides of the caliper...
When all 6 pistons move freely, compress pistons properly, install pads (without pin by pumping lever) and repeat on left hand side until satisfied that all pistons are free. remove brake pads and crack the seal on the brake line banjo bolt.
Remove the 2 caliper mounting bolts (12mm) and pull the caliper off the rotor. Over a container, remove banjo bolt, being
careful of the crush washers, set to one side.
With the caliper removed from bike remove the 4 cap heads holding the 2 parts together. pull apart.
Carefully remove the 2 rubber washers
Place a rag over the pistons, and a finger over one bypass hole, Blast compressed air into the other hole. 1 piston will pop out.
With a rag in between long nose pliers jaws (BE VERY GENTLE), gently grasp the others and tease out DO NOT APPLY TOO MUCH PRESSURE!!!!
If 1 will not come out, reinstall the other 2 pistons, cover them with a piece of wood, clamp with G clamp, cover in a rag and blast compressed air into one hole whilst covering the other hole....be careful that compressed air is
pretty forceful!! piston may pop out with extreme force.....cover in a rag in your hand. it
doesn't hurt. Just makes a loud pop!!.
Check the outer dust and dirt seal for integrity.....it should be okay, mine were "welded" to the pistons with salt corrosion. but after cleaning they turned out okay, so I
reinstalled. But next time I will have a new set ready....
Check the pistons for scores or wear....mine had marks around the pistons that indicated they had been rattling in the calipers......I shall go to
the dealer and find out about that.
I used my finger nail to remove most of the hard gunk, then brake fluid to get rid of the rest. the calipers were
severely corroded, so a scrape with a flat ended screwdriver and a few blasts with brake cleaner got rid of all the crud, finally turning the caliper upside down and blasting the cleaner up into the bores to remove all traces of dirt particles. Compressed air helps too.
The caliper halves MUST be spotless before you start to rebuild them.
Here goes the bit about replacing seals.......if you want to, mine were okay. Next time I shall replace
them. Inspect them. any doubt, replace them....brakes are kind of important.
Wipe a little brake fluid around the pistons, push into the bore, there is a step, so when you hit it, wiggle the piston around a bit and it will go in. the top and middle pistons are the same size so I changed them around....
push the pistons right down into the bore.
clean and reinstall the rubber washers, you will see one half of the caliper has a deeper recess for the washer than the other.
Line up the other half on top, insert cap heads and tighten.
Clean the banjo bolt and crush washer (it is recommended that you fit new crush washers.... mine have lasted 3 strips and still
don't leak....so you decide, but best to have them eh??
Refit brake line to caliper, and fit caliper to mount.
Repeat process with LH Side caliper
So, both calipers installed, now clean the edges of the brake pads, reinstall them, not forgetting to copper slip the holding pin..
Torque the cap head bolts and caliper mounting bolts.
I use a syringe and tube...
Fill the master cylinder with fluid, attach hose to RH Side nipple, open nipple and suck fluid,
keeping the reservoir topped up. When pure fluid comes out, close nipple and do same on LHS....
When what comes out is pure fluid, bleed conventionally, starting at the RH Side caliper.. pumping lever and holding, undoing nipple, tightening nipple then pumping and repeating
until no air comes out of tube.
Do same on LH Side
A couple more on RH Side then LH Side (just to be sure ;) remembering to keep fluid level topped up at all times (if you get to see the hole in the bottom of the
master cylinder without fluid in it, you have air in the system and nust start bleeding all over again...
Wipe clean master cylinder diaphragm, and covers, reinstall.
Wipe any spilt fluid...if copious amounts on paint work wash with soapy water..
Pump lever top ensure all brakes are working correctly....
If they are not, you have done something wrong.. check your work.
REAR BRAKE is similar, except only 2 pistons.... remove the same way, remove bracing strut.
to get to rear master cylinder you must remove rear tail section......easy, 8
push connectors, 2 Frankenstein bolts, 2 crosshead crews, 2
Only difference is bleeding...DON'T USE PEDAL. Start by attaching syringe to
LH Side nipple, this draws the fluid through he caliper. I did it before I installed on the rotor, so that
LH Side nipple was up most...thus it had all the air......then I installed on rotor, added pads and pins, then I could use the brake lever.
WHILE YOU ARE AT IT
The rear brake lever gets very dirty and the pivot gets clogged.
Undo the 3 big cap heads holding the rear set on. rotate, and remove the split pin and clevis pin from the rear of the lever.
Remove the 2 springs
Using the circlip pliers remove the clip, washer, then the brake lever.
Clean the pivot and inside the lever, wipe with the green high temp, waterproof mechanical grease, reinstall.....check you
haven't dislodged electrical connection on the top.....
Pump brakes to make sure they all work....