Need some help and info

650ed wrote:

The_Proletariat wrote: You want a 12.5mm or 12.7mm master cylinder. Replace the brake line as well. A new braided line is not expensive.

650ed wrote: the correct bore size for a single front disk brake system is 14mm

A 14mm master cylinder may cause high brake lever effort.

I don't understand your statement. I am under the impression that the original MC bore for the single disk system shown is 14mm, so why would that cause high brake lever effort. Didn't every KZ bike with a single front disk come from the factory with a 14mm bore? Ed

Am also under the impression that the original MC bore for the single disk system shown is 14mm, and that every KZ bike with a single front disk came from the factory with a 14mm bore.

Would closely inspect the underside of the master cylinder at hand to see if it has the size embossed, such as 14 MM or possibly a smaller size.

Could also use a caliper to measure the bore of the master cylinder at hand to see whether it's a 14mm or something smaller.

A master cylinder larger than stock will produce a wooden feel requiring a harder squeeze than needed with the stock size.
This is usually the case where a larger size m/c is used to replace the stock m/c while leaving the single disc front brake.
In general, dual front disc brake uses a larger m/c than does a single front disc brake.
When adding a 2nd disc to a stock single disc front wheel brake, the larger m/c should also be fitted to replace the stock m/c.

A master cylinder smaller than stock will be over-sensitive whereby an emergency brake application could result in front wheel lock-up and loss of control, especially on wet or damp pavement, or dirt road, or oil patch on road, or leaves on the road, etc., all undesirable, especially when riding leaned over in a curve.
This is usually the case where the stock m/c with stock single disc front brake is kept when adding a 2nd disc to the front brake.

Note that the original Z1 came with a single front disc and a 14mm m/c.
A kit was available from the factory to convert the Z1's stock single disc front brake to a dual disc front brake system.
Along with the additional rotor, lines, caliper, etc., the factory kit also included a larger 5/8" m/c.

Good Fortune!

So could I put a Honda oe 14mm piston on there? www.amazon.com/gp/aw/d/B01CCN17BI/ref=mp...pFzNPf93L&ref=plSrch

Keep in mind if you do not use Kawasaki parts on your Kawasaki you are going to need to make modifications to accommodate your front brake light switch and your clutch lever / neutral lockout switch because the new units will not match your bike's setup. Ed

Well to buy oem Kawasaki from Kawasaki the dealer near me wants almost $500 for one

Have you checked eBay?
Stee

Patton wrote:

650ed wrote:

The_Proletariat wrote: You want a 12.5mm or 12.7mm master cylinder. Replace the brake line as well. A new braided line is not expensive.

650ed wrote: the correct bore size for a single front disk brake system is 14mm

A 14mm master cylinder may cause high brake lever effort.

I don't understand your statement. I am under the impression that the original MC bore for the single disk system shown is 14mm, so why would that cause high brake lever effort. Didn't every KZ bike with a single front disk come from the factory with a 14mm bore? Ed

Am also under the impression that the original MC bore for the single disk system shown is 14mm, and that every KZ bike with a single front disk came from the factory with a 14mm bore.

Would closely inspect the underside of the master cylinder at hand to see if it has the size embossed, such as 14 MM or possibly a smaller size.

Could also use a caliper to measure the bore of the master cylinder at hand to see whether it's a 14mm or something smaller.

A master cylinder larger than stock will produce a wooden feel requiring a harder squeeze than needed with the stock size.
This is usually the case where a larger size m/c is used to replace the stock m/c while leaving the single disc front brake.
In general, dual front disc brake uses a larger m/c than does a single front disc brake.
When adding a 2nd disc to a stock single disc front wheel brake, the larger m/c should also be fitted to replace the stock m/c.

A master cylinder smaller than stock will be over-sensitive whereby an emergency brake application could result in front wheel lock-up and loss of control, especially on wet or damp pavement, or dirt road, or oil patch on road, or leaves on the road, etc., all undesirable, especially when riding leaned over in a curve.
This is usually the case where the stock m/c with stock single disc front brake is kept when adding a 2nd disc to the front brake.

Note that the original Z1 came with a single front disc and a 14mm m/c.
A kit was available from the factory to convert the Z1's stock single disc front brake to a dual disc front brake system.
Along with the additional rotor, lines, caliper, etc., the factory kit also included a larger 5/8" m/c.

Good Fortune!

The OE master cylinder on my 1982 KZ550C3 is cast with large raised numbers "1/2" which I assume to be the bore/piston size in inches, and in smaller print "1/9" which I assume to be the hydraulic ratio. 1/2 in = 12.7mm.

At the end of the day, I don't think he would have a problem with a 14mm master cylinder, but 12.7mm is the factory size for a KZ550C.

I still have my original master cylinder if the OP needs one.

Does your original still work if so that would be great!

BrimmyP wrote: Does your original still work if so that would be great!

It is not in great condition appearance wise but it worked when I took it off 2 years ago. I bought superbike bars and it didn't fit.

what master cylinder did u go with? I've got euro bars on mine and want a smaller unit on the handle bars.

No eBay APP ID and/or Cert ID defined in Kunena configurationNo eBay APP ID and/or Cert ID defined in Kunena configuration

lightitup wrote: what master cylinder did u go with? I've got euro bars on mine and want a smaller unit on the handle bars.

I used one like this. There are a bunch of sellers selling this piece. I had to supply crush washers because it came with rubber washers, not copper.

If you don't want chinese something like this would work

The factory service manual for the 550 states the front master bore for a single disc bike is 14mm and 16mm for a dual front (Euro model?).

EDIT: found a reference to the 1981 bikes using a 12.8mm bore master for single brake bikes. I assume that carried forward for 1982.

Nessism wrote: The factory service manual for the 550 states the front master bore for a single disc bike is 14mm and 16mm for a dual front (Euro model?).

Attachment not found

That chart is for the original 550 model, maybe A? The 550 C has different brakes which is in the supplements in the back of the manual.