Rear disc m/c upgrade GPZ750

I know, why worry about the rear master cylinder?

Well. My bikes rear brake never really worked last year. Not a real big thing, I use it to hold the bike on hills and to keep my brake light activated when I am at a stop light. The light wasn't activating right, so I took time to look into it, and the boot had torn, letting water in until the c-clip rusted out and everything was held together by said boot.

Real ugly.

My philosophy on my bike: Kawasaki did not change alot of stuff over the years. Frame: yes. Suspension: to a point. Wheels, sure. But everything can be grafted together with a reasonable amount of work. Some is plug and play, look at my list of mods.

Add a 250 Ninja rear master cylinder. Bolted right up, had to use the original brake line for the length, and had to cut the res. line a little to get the correct length to the mounting point. All told, maybe an hour to change. Looks like the same m/c was used on all 250 ninjas up to 08 so far.

And the new m/c? much much better design. No big rubber boot. The res. line was much more meaty, probably flows more, like that means anything.

And at $15 shipped off of ebay, cheaper than a rebuild kit.

I am working on a project bike and have been thinking about doing much the same thing. I pretty much rebuilt the rear master cylinder a few years ago and if memory serves, I changed the seal on the plunger. The thing still leaks so I suspect there are gouges in the bore. Not much point honing and rebuilding as it will leak again. I have other master cylinders sitting around I think but a newer one would probably be a better idea. thanks for the idea. The rebuild kit for one of the rear master cylinders on my bike (from a 78 KZ1000) is over $60! wg

Yes, WG, I bet that the same m/c will work for you: I went by eyeball, but I will see if I can get a mount to mount measurement later.

I am swapping the wheels on my 74 z1 900 with the mag's from an ltd 1000. Now, the front brakes are off of a 1986 GPZ 900, the rear brake is the stock tld 1000, but the rear master cylinder is off of a 2003 suzuki GSXR 600. I had to make a mount for the rear m/c, because the bike originally had a drum brake in the back. For this, i just ran a peice of metal from the 2 rear engine mounting bolts to the gsxr master cylinder.