My rear brake is too bad and needs improving

I recently put my KZ1000 1982 CSR on its side at low speed because I over did it with the front brake. I reviewed my riding and think I am using the front brake too much in favour of the rear brake, because the rear brake is just not effective enough. Does anybody know of some improvements I can do to the brakes. All is pretty much standard at the moment, no special pads, the disc is new since the old had a crack.
Any suggestions?

did you replace the pads and flush the old fluid out yet?

The pads and fluid are as new as the disk.

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H1Vindicator wrote:

So you probably ought to replace the brake line too.

If the line is not leaking, how would this improve the braking efficiency?

I use my rear brake so much that the disk is rusted. Meaning, never. sometimes I put pressure on it when I am sitting in traffic and I want to let go of my handle bars. On those bikes the brake was very ineffective because Kawasaki actually went to a smaller disk over earlier bikes. I am not quite sure why you would put your bike down because of over use of your front. I honestly never use my rear on my 81 GPz1100 and the rear brake on my 79 KZ1300 has not worked in over 15 years because of the rear master cylinder rusting out internally. Your brake may have lost some of its efficiency possibly for a couple of reasons. These reasons may include, air in the brake system, sludge in the system, moisture in the system, corrosion on the piston, and others.

Yes you should get a least a rebuild kit for the caliper, but really you should kit the master as well. The piston may be hanging in the bore of the caliper. What sort of pads did you use to replace your worn ones? There are different qualities and friction materials, cheap pads all most always don't stop as well.
But I agree with using the front brake for sure. I try to keep pressure on the rear while pulling the front, 25% rear 75% front or something.

Reportedly, more rear brake use reduces front tire cupping.

Good Fortune!

the manufacters recomend replacing the rubber brake lines every two to three years because of the properties of brake fluid the rubber gets eroded away from the inside out and they lose structral integrity cause excess flex. which mean your not getting full amounts of fluid and pressure to the piston in the caliper. one easy way around this problem is to replace with steel braided line that will make your brake very positive. bt as some other people have said please do not relie on the back brake it only gets about 25% of the braking force the front brakes do. practice panic stop situations with the front brake only , the rear brake only and both together and see for your self which stops you quicker. i very rarly use the back brake my self during straight line stops mostly what i use the back for is trail braking in corners when i'm performance riding. the front brake if applied aggressivly in a corner can cause problems but most times i've seen someone go down and blame the brakes it was because they where either to aggressive or werent thinking far enough down the road myself included.

Schorly wrote:

The pads and fluid are as new as the disk.

If the disc was used (and not resurfaced) it will take a while for the pads to "set in" and get full braking on it.

The disk, the pads and the fluid was changed at the same time. I didn’t change the hoses and may have not flushed the system through enough to get rid of all the debris. So I will do this next and see if the braking improves. If not I might have to live with the inefficiency of the rear brake as it has been mentioned by other comments.

Schorly wrote:

The disk, the pads and the fluid was changed at the same time.

If you installed pads against a used disc, those pads take a while to cut in to match the rotor surface. Until that happens, you will have significantly reduced braking power.

If you got air in the lines, that will also give you a soft pedal and very little braking effect.