Rear Brake lockup

I'm glad it worked out well for you. Keep the shney side up and don't be a stranger here.

i have same problem. i cleaned mc and open the small hole. caliper cleaned piston moves when bralke line off.  . but still squeeze  and disc color is purple now . does anyone have idea?

Could be a couple things, now that you're sure the Master cylinder is clear. I assume you're referring to the rear because you said "the" disc is turning purple. Piston in caliper can get hung-up too of course or a sticky pivot for brake pedal. Also since it seems you've had it apart, leave some free-play for the pedal to master rod adjustment. You should be able to move the pushrod around a bit upon final adjustment. And finally, footwear, you could unknowingly be compressing the brake pedal while riding? Platform/Uggs shoes can be cool but don't cotton well to burning rubber, ha.  

yes rear brake. no pushing the brake . but piston moves freely when brake line off. when connectting brake line push the brake and quit it . tire hard to turn. it still brakes

Does it release if you open the bleed nipple

Page 1 of the below link shows master cylinder operation (I know it's for a front but the principle is the same)

Front Master Cylinder Q? - KZRider Forum - KZRider, KZ, Z1 & Z Motorcycle Enthusiast's Forum

i will check today. and reply 

no it dosnt release and i measure the piston seal inner diameter comes 43mm and piston 42.7mm ?  put in the caliper seat comes to near piston diameter. and some ones at the forum hayabusa caliper kit fit it do you know about it?

kawastrtfgtr wrote:

no it dosnt release and i measure the piston seal inner diameter comes 44mm and piston 39.5mm ?  put in the caliper seat comes to near piston diameter. and some ones at the forum hayabusa caliper kit fit it do you know about it?

I assume you are talking about the calliper piston ? don't know about the Hayabusa thing but there are plenty of suppliers for the correct seal kit for Kawasaki - also don't forget the calliper needs to slide freely on the mounting pins or the opposing pad will stay applied. Is one side of the disc colouring up more than the other (inner or outer)
With the piston pushed back and the pads removed the body of the calliper should slide freely on these pins


 

they work well sldes caliper . but the piston side shoe pad burns the other shoepad doesnt

should i cange the caliper piston seal

Did you check the free play on the pedal that asphalt suggested - if that's ok it does seem to be a calliper problem

yes i did. when i change the seal i will tell .