Replacing Master Cylinder after Brakes Locked Up

About 2 weeks ago, I was riding along and my back brakes locked up on me. Luckily I was not going very fast or riding around a curve.

Had a local shop rebuild the brakes, front and back. They put new pads on, rebuilt the calipers, supposedly blead the lines and cleaned everything up.

Lucky me. I was out riding Sunday and the damn things locked up on me again. I called the shop back and they apologized and told me I probably need a master cylinder rebuild kit.

Well, I pretty much told them. I'm not coming back for anymore service and I will just do it myself.

Any big issues I should look out for?

My friend is a shade tree mechanic and he will be helping me out.

Would adjust to enlarge the free-space gap where pushrod enters master cylinder.

Good Luck!

Do what Patton said. If you don't know how, and if you have the Kawasaki factory service manual, look at the instructions for adjusting the brake pedal. It describes how to adjust the gap. If that doesn't fix it you may have a brake line problem or some serious gunk in the system. Have you changed brake fluid on a regular basis? Ed

The brake fluid was completely flushed when they rebuilt the calipers and put new pads on.

After reading on this board and talking to the original owner of the bike (the jag off I bought it from can die / lying dick) I am going to replace the rubber brake line with a stainless model.

Orginal owner indicated that is probably the issue as it happened to him prior to selling it to the dick above.

He told the dick that there was an issue and he should replaced the line.

Dick face indicated nothing was wrong with the bike and it was a solid 8 out of 10. Only cosmetic issues.

Well, live and learn.

I will post my results when I tear it down this weekend.

P.S. Guy in Columbia, Illinois - FO.

The brakes seem to be working fine.

Replaced the original brake line with a stainless line from Z1 Enterprises.

Also rebuilt the master cylinder.

Did not adjust the pushrod as things seem to be working ok.

Couldn't get the brake fluid to flow through the brake line so I bought a hand vac. Worked great.

May have to bleed brakes again as I didn't get ride the bike for a very long distance due to the fact it RAINS every day in the Midwest.

Sometimes you just have to do it yourself so you know that its right. Sounds like you are making progress.

I had my front lock up on me before I changed the brake fluid (ended up tearing the pads off to ride it home on the back brake, fun fun!).

Point of this is that when I took everything apart the return hole in the master cylinder was clogged up in a bad way. So bad in fact that at first I didn't see the hole at all! It blended right in with the other gunk in the reservoir. Took a piece of wire to it, brake cleaner and everything and cleaned it out real good, haven't had a problem since!

So, moral of the story, i'd double check the return hole. It's VERY easy to miss if you don't know what to look for.

Good luck! Not a fun problem to have!