82 kz750e brake caliper

so i just got this bike as a gift from my pops bike has 8k orig miles and when its worm out the rear caliper drags untill its bled any idea on why? or would rebuilding it or just replacing it be best

Welcome aboard! I wouldn't even consider replacing it. Start by flushing the brake system with fresh brake fluid until the fluid is clear. If that doesn't fix it you make need to disassemble and clean out any old muck that may be in there. Ed

i have flushed it a few times. if i take it apart are there any rebuild kits out there i have looked and no luck

These folks say they have front and rear caliper rebuild kits for the KZ750-E3. Go to the link below and click on "Our Products." Then click on "Rebuild Kits" (near bottom of page). Then click on "2008-09 Brake Caliper Rebuild Kits/ Pistons /Pad Springs" (I know the 2008-09 seems weird). Then look at the 4th item on page 293. They also have the front and rear master cylinder rebuild kits for the KZ750-E3. I hope this helps. Ed


www.cyclebrakes.com

BxRad925 wrote: so i just got this bike as a gift from my pops bike has 8k orig miles and when its worm out the rear caliper drags untill its bled any idea on why? or would rebuilding it or just replacing it be best

Sounds like the Master Cylinder, the Fluid Return Port is blocked. This can be very hard to see on some configurations. Basically there are two ports inside the Master, one for Fluid feed to the piston, and one for fluid return. If the caliper is not returning, but will when the bleeder is opened, I would suspect the port in the Master. Or possibly the Pedal, and Pushrod are not returning completely. If the Pedal doesn't return fully, taking pressure off of the rod and piston, it will hold pressure in the line/ caliper.

CycleBrakes may have the kits, but note that the catalogue looks to be old to my eye, so it may not be updated & they may not have everything listed.

Z1Enterprises has a K&L caliper rebuild kit, but the K&L piston is listed as discontinued.
However, the oem piston is an Active part at Kawasaki.com. If it's available, Z1Ent can get it. Or RonAyers etc.

You should replace the brake line if it's the original rubber part. Z1 has Goodridge ss lines & fittings, but something like the Galfer stuff at Cylcebrakes.com would be simpler & there would be fewer chances for leaks.

I would go ahead & refurbish the front brake as well.

i have no problems with front at all. but thank you all for the help i will dig deeper into finding out whats causing it