rear caliper question?????

i m taking bike in for a state inspection tommorow and i was looking it over and i noticed that when i engage rear lever,caliper moves outboard about a millimeter or two....is this normal and something i never noticed before?
i have developed a squeal at times also...are the two symptoms indicative of a stuck piston?....just wondering...thanks......keith

It's normal for calipers to move as the brake disc wears.

The squeal may be caused by buildup of brake dust/disc material. Sometimes the pads can be lightly sanded to reduce squeal. Auto parts stores sell a disc brake quiet you apply to the back side of the brake pads to deaden the vibration during braking.I'd check the rear caliper for operation and clean the system.

MFolks wrote:

It's normal for calipers to move as the brake disc wears.

The squeal may be caused by buildup of brake dust/disc material. Sometimes the pads can be lightly sanded to reduce squeal. Auto parts stores sell a disc brake quiet you apply to the back side of the brake pads to deaden the vibration during braking.I'd check the rear caliper for operation and clean the system.

thanks....pads have about 500 miles on them and i didnt put any anti squeal on the back....not a biggee....just wondering about the movement.....

The calipers do move, as they are floating on the mounting bolts.
The piston and pads position limit the amount of movement.
When rebuilding and cleaning the calipers, then reinstalling them with the piston and pad moved almost all the way in, the caliper has tons of movement until you pump up the system and the piston and pad move out.

Keith, my front calipers have single pistons, and the calipers do indead float to compensate for inner pad wear, tho discernable motion is minute. my rear caliper (kz1000 A1) however is solid mount to it's carrior and has pistons on both inside and out, which receive same pressure from master. I believe any motion there would be from a frozen piston, or a pad incorrectly located. causing the carrior to deflect. (if your's is same) have a look and see If you agree. Luck G

gane wrote:

Keith, my front calipers have single pistons, and the calipers do indead float to compensate for inner pad wear, tho discernable motion is minute. my rear caliper (kz1000 A1) however is solid mount to it's carrior and has pistons on both inside and out, which receive same pressure from master. I believe any motion there would be from a frozen piston, or a pad incorrectly located. causing the carrior to deflect. (if your's is same) have a look and see If you agree. Luck G

i m thinking due to the fact the rears are double piston and solid mount, i should nt see any discernable movement....i understand movement with a single piston.....i ll keep an eye on it and probably get a rebuild kit for back caliper.....thanks everyone.....

I didn't relize the '78 kz1000's came with two piston calipers. I thought they were the same single piston calipers as either the '78 or '79 KZ650s.

rstnick wrote:

I didn't relize the '78 kz1000's came with two piston calipers. I thought they were the same single piston calipers as either the '78 or '79 KZ650s.

not a biggee....all part of the learning curve....thanks for the input......

rstnick wrote:

I didn't relize the '78 kz1000's came with two piston calipers. I thought they were the same single piston calipers as either the '78 or '79 KZ650s.

upon further investigation they are single piston...
should i hear light dragging when wheeling the bike around?..can these be fixed?...can the piston be cleaned up for smoother action?....thanks...keith...