Guys

You are my last hope of getting my brakes working on a 2000 ZX12r A1

Basically, my brake lever would pull all way back to bars. On MOT I had to have front EBC discs replaced under warranty as they were warped and I also had goodridge lines installed (thinking the spongy brake was my old lines).

With a couple of new pistons the dealer had fitted, new organic pads (to scrub zinc plate off iron discs), pad slide pins and fluid bleed I picked picked up the bike and the brakes were razor sharp.

Now some 2 weeks later I can pull the lever back to the bar again..........

Is it something as simple as air in the system ?, if so where is this air coming from ?............... could if be a duff master cylindr assembly ?

When ever the bikes comes back from a garage the brakes are perfect.... couple week later they are gone again. I find clamping the lever overnight restores them to some extent, but a few hours later it bad again

I'm at a loss tbh... the dealer ever tried to sell me a new set of OEM calipers to fix the problem.

 

Try replacing the4 brake fluid with all new fluid. Drain all the fluid out of the lines completely then put new fluid in. if the dealer added fluid that was different than the fluid that was already in the motorcycle your brakes can do what you are saying. Brake fluid will heat at different temperatures and having 2 different types of fluid will just make them go squishy. If you have already done this and bled the breaks and the problem still happens next step may be cleaning your calipers or replacing them.

 

sounds like a seal is adding air in the system some where.

 

I would say air is getting into the system. make sure your brake lines are tight and not leaking. then try putting in new brake fluid and bleed them real good. if that doesn't help go with the new calipers.