Master Cylinder for 1980 KZ1000 E2 Shaft

Hi gang,

I'm the typical new forum member who joins up and immediately begins asking questions before actually contributing anything to the forum myself...

I have a 1980 KZ 1000 E2 Shaft. I've had it for several months and the front brake feels a little soft. I first bled the lines and still had the same feel. I then rebuilt the master cylinder, bled the lines again, and I have the same problem. The brake will work, however, as stated, it feels soft. If I squeeze the lever quickly it will meet with resistance. But if I squeeze the lever slowly it will actually pull all the way in to the grip (haven't done this while riding, just in the garage). Is it possible that the inside wall of my master cylinder is pitted or scarred and allowing fluid to slowly escape? I do not appear to be losing fluid anywhere (level remains constant, no wet spots on the lines or bleeder valves).

*edit* I've also noticed that when I squeeze the lever slowly I can see the fluid level rise slightly through the reservoir window. Don't know if this is normal, I've never paid attention on my previous bikes. ****

Sorry for the long post, just trying to give as much info. as possible. I've priced the master cylinder assembly at $260. Any ideas on one from a different bike that might be a little more affordable but would still accept my bolt size and fit my bars?

See, told you I was one of those typical new members...

I have purchased this on Ebay, and surprisingly it works well. I also purchased SS brake lines, since I upgraded the whole front end.

cgi.ebay.com/ebaymotors/FRONT-BRAKE-MAST...7C39%3A1%7C72%3A1171

Good Luck

Perhaps the primary cup is for whatever reason not completely sealing when pushing fluid into the line.

This could be attributable to something with regard to the cup, or perhaps to excessive pitting in the bore.

Good Luck!

Royal1MC wrote:

I have purchased this on Ebay, and surprisingly it works well. I also purchased SS brake lines, since I upgraded the whole front end.

cgi.ebay.com/ebaymotors/FRONT-BRAKE-MAST...7C39%3A1%7C72%3A1171

Good Luck

Thanks for the tip, Royal1MC. I actually saw that on e-bay the other day and was wondering. Even if I have to replace the entire brake line (like you said, SS would probably be the way to go) I would come out ahead vs. buying OEM.

I may pull the guts out and double check everything before pulling the trigger on a whole new cylinder.

Again, thanks for the replies, guys.

A rebuild kit for the master cylinder is available from Z1E, which includes a new piston, etc.

Click here > M/C Kit from Z1E

Z1E also carries a large variety of brake hoses.
Brake Hoses Galore

Okay to gently dress mild pitting inside bore with very fine wet-sand.

Good Luck!

Patton wrote:

A rebuild kit for the master cylinder is available from Z1E, which includes a new piston, etc.

Click here > M/C Kit from Z1E

Z1E also carries a large variety of brake hoses.
Brake Hoses Galore

Okay to gently dress mild pitting inside bore with very fine wet-sand.

Good Luck!

Thanks, Patton. I did already install a rebuild kit with the piston, cup, and seals. Unfortunately, it didn't fix my problem (although the old parts were in pretty bad shape and I'm sure it didn't hurt). I think pitting in the bore may be my problem.

It stops fairly good right now, but something isn't quite right. You just can't quite enjoy a ride like you should when something feels wrong while stopping.