I understand, your present master cylinder will be too small for the amount of fluid needed. You will require either a spliter hose to power both calipers, or a longer "Banjo" bolt, so individual hoses can be used. If you can get a hand powered vacuum pump(I use a brand called Mityvac), it will make brake bleeding easier. Also new bleeder bolts, on the calipers, with the built in one way valves.

Brake Lines
http://www.galferusa.com/html/ss_line_kits.html
Inline tube The brake plumbing experts
Spiegler Performance Parts - Motorcycle Brake Line Kits
HEL Performance USA | Stainless Steel Braided Brake Lines
http://www.russellperformance.com/metric_two-line.shtml
http://www.goodridge.co.uk/motorcycle-brake-lines/kawasaki.htm
Galfer Brake Lines
Brake Line Bleeders
Speed Bleeder Sizes
Motorcycle Application Chart
Pingel Enterprise, Inc. ? High Quality Motorcycle Performance Products
Spiegler Performance Parts - Speed Bleeder | Motorcycle Brake Bleeding

 

If you go with the popular Stainless Steel Braided Hose, be careful, as it will act like a slow speed file, cutting through paint, wiring, and other tubing and lines, as it wears away. The best brake lines have a heatshrink coating, but black spiral wrap works good for this too, and can be found at most electrical supply places, and some hardware stores.

 

If you go with the popular Stainless Steel Braided Hose, be careful, as it will act like a slow speed file, cutting through paint, wiring, and other tubing and lines, as it wears away. The best brake lines have a heatshrink coating, but black spiral wrap works good for this too, and can be found at most electrical supply places, and some hardware stores.

Thank you. What about the disc and caliper?

 

I'd ask here: Z1 Enterprises, Inc. - Specializing in Vintage Japanese Motorcycle Parts, including New Old Stock & aftermarket parts. | www.z1enterprises.com

 

Is the bike a 650B? Remove the right side dust cover to see if there are bolt holes for adding a disk.
The needed info might be available at the KZ650.Info site's forum.