Z1000J front brake pads replacement

Hi

I have a 1981 Z1000J(KZ in US)and I am in the process of replacing the front brake pads on both calipers.

The calipers come off the fork in two parts. The one part contains the main piston that does the braking. The other is a simpler device that bolts onto the fork and then the main brake caliper bolts onto that. It contains two small 'pistons' that return the brake caliper to position after brakes were applied (bit difficult to explain without pictures)

These two small return pistons are mounted with rubber surrounds and some oil/grease came out when I disassembled them.

What oil/grease/fluid must I replace here when I reassemble???

Any help is most welcome.

Thanks

Herman... Calipers on a KZ come in two parts held together by large socket head bolts. It is generally not necessary to split the halves to change the brake pads. To change pads, there are two small steel rods that go through holes in the top of the pads. These rods are held in place by small cotter pins (actually not cotter pins but I can't recall what these type pins are called). Anyway, since you have the things apart and the caliper pistons are out, wipe out the bores that the pistons sat in. There should be NOTHING inside those bores... certainly don't put anything in there. Put the pistons back in and lever them back into the bores... it will be a hard push but they will go if they came out. Anyway, put the two caliper halves back together making sure you put the small washer back in place where the fluid goes through the halves else the caliper will leak.

Now, remove the two cotter pins and pull out the small steel rods; the brake pads will just drop out. Put the new pads in place. There will be a small clip that is used to keep the pads from rattling. Make sure you put these clips (one per pad) back in place as the rods slide above the arms on the clip and that is what keeps the clip in place. Some bikes will also have skinny steel plates in back of the pads to keep them from rattling... not sure about your model. Anyway, once you have the steel rods back in place, put the cotter pins back in. You may need to lever the pads apart some to get them to fit back over your rotor. Put the caliper back on the bike. Before you decide to test ride, pump the brake handle till you regain pressure as pressure will be lost (NO BRAKE!!!!) initially from spreading the pads.

I don't believe you want to split the calipers next time you change brake pads. It really isn't necessary to remove the calipers from the bike either... it is always necessary to pump up a brake after changing pads.

I take it you are talking about parts 43045/43045A in the diagram below (in the red box)? They are not pistons, just the rods that the caliper slides on, no big mystery there. If the caliper body moves freely when you press and release the brake lever, don´t worry about them, if not clean them up and lube them with a drop of engine oil or sewing machine oil - don´t use too much oil, you don´t want them dripping on your rotors.

Many thanks to WiredGeorge and OnkelB for the advice. The calipers are of the variety in the diagram that OnkelB supplied and guestimated the correct part numbers.

I took them apart, cleaned the lot out good and applied a bit of general purpose grease (Castrol LM grease) to the shafts of both the parts 43045 and 43045A.

I bled the whole system properly. Will still need to bed the pads down, but pads are dragging a bit at the moment. If problem persists, I will remove the grease and replace with oil.

Will keep you posted.

Hi

Just a quick report: The pads are bedded down nicely - I can stop again (brake pads still cheaper than coffins) and the calipers are sliding freely on the grease-job. No rattles, no sticking and no pads dragging.

Thanks again. Will post photos of the beast on the open forum soon.

h

81 KZ440LTD
81 KZ1000J