For this you will need :-
A caliper rebuild kit
8mm Combination spanner
12mm Combination spanner
A tool to fit your banjo bolt
An M8 nut and bolt
First thing to do is clean the rear end (oooerr), I know I haven't but I was in a bit of a hurry.
Once clean and dry push piston all the way back into the caliper body (if you are doing this repair you might find this difficult and requires the use of a G clamp or similar) then loosen the two mounting pins and the bleed nipple, now use adequate protection around swingarm area (I used jay cloths) to prevent brake fluid spills.
Get your M8 nut n bolt ready.
Undo banjo bolt and remove
Raise brake line and put nut and bolt through and tighten, this will prevent excess fluid loss and help with bleeding when re-assembling.
Remove rear pin
and rotate caliper clockwise(watch out for the brake fluid)
then withdraw caliper and remaining pin from caliper mount.
Removing the piston from the caliper is the hardest part of this job which is why I did it in work(access to an airline).
If you have the facility, compressed air is the easiest and quickest way to do this, just tighten the bleed nipple and apply compressed air to the hole you took the brake line from (see below).
If you don't have access to an air line it is possible to get something into the banjo bolt hole ( be careful not to damage the thread) and push out the piston far enough to be able to grab it from the outside with a pair of pliers and withdraw whilst twisting.
Once the piston is out remove the bleed nipple again.
This is what you will find
And the old piston compared to the new one.
Now remove both seals (Large oil seal and narrower dust seal) and wipe off excess brake fluid, then wash in hot soapy water until clean and dry thouroughly.
Once dry you will need to clean out both grooves (I used a small screwdriver) because there is a build up of oxides in there that need to be removed, be careful not to damage these grooves or the new seals will get damaged when you put them in. Also use an abrasive sponge (like the one in the kitchen) and clean the small face between where the the two seals fit.
The kit will comprise of these items,
1 oil seal
1 dust seal
1 piston
1 small pack of grease.
First put a small amount of grease on both seals and put into respective grooves, be careful with the dust seal (narrower one) as it is easy to get this twisted, then apply a light smear of grease to the area between the two seals and also a light smear onto the piston.
Now carefully push piston into the caliper, this can be a little tricky so be patient, it needs to go in squarely or it can get stuck.
Amost home free.
At this stage it might pay to remove the rubber boots from the caliper mount and clean and grease them and also clean out the holes in the mount an put some grease in there too, but be warned getting these boots back on is not for the short tempered.
After cleaning the boots( if you do) clean and grease the pins
and replace caliper onto bike.
Replace banjo(using new copper washers if required) and bleed nipple, bleed brakes(I always run two master cylinders of fluid through) and clean off any remaining brake fluid.
You should end up with something like this
I usually use the bike for about 100 miles then re-bleed as the seals will have had time to 'bed in' and you might find they have gone a little spongey.
Whole job took about 1hr 45mins
Edited by dapleb, 24 June 2012 - 07:38 am.
Added model details to title