1996 ZX6R: Brake rebuild

[Mike]

Hi all,

Having some trouble with the brakes on my 1996 ZX6R.

Over the last couple of weeks I've been rebuilding the front brakes on my track bike. I've put new lines on, new MC kit and a new seals kit in the calipers. The only problem is now I can't get decent brake pressure.

The lever gets about one inch away from the bar and feels good, but up until that point I have nothing. I've pulled apart the MC again, check everything for leaks, all the pistons in the calipers are moving out and in freely. Nothing appears to be leaking anywhere.

I just can't get good lever pressure. I've literally lost count of how many hours of spent trying to bleed them. One thing I did notice is that in the fluid reservoir there are two holes. As soon as you touch the brake lever fluid spurts up out of the smaller hole quickly. Is this normal? Apart from that I'm a bit lost as to where to go from here, besides taking it to a mechanic.

Any thoughts, suggestions or comments? I'm all ears.

Cheers,
Mike.

[robracer]

Mike you probably still have air in the system, when you have fresh lines you can get air trapped, try building up pressure then snap open the bleed nipple when squeezing the lever, then snap it closed & build up pressure again, this will force air bubbles towards the bleed nipple as you repeat the process.
Another thing to try is to snap open the top banjo bolt when squeezing the lever then snap it closed before the lever hits the bar, this will force out the trapped air at the top of the line. Standard master cylinder kits will normally spurt out the fluid from the resiviour its fine, radial kits wont because it is a remote system. BTW where are you located?

[Mike]

Thanks Rob. Have tried from the top banjo bolt with no luck. Still have the same result. Might have to take it to a professional.

BTW, in the ACT.

[matt6]

Have you tried tying the lever back to the bar and leaving it overnight? Not too sure of the technicalities of why it works, but on my F1 it made a big improvement to lever feel.

[robracer]

Have you tried tying the lever back to the bar and leaving it overnight? Not too sure of the technicalities of why it works, but on my F1 it made a big improvement to lever feel.

It leaves the MC open for any bubbles to travel back to the resivoir... well that what I got told many years ago mind you I dont think it works for radial MC's

[Mike]

Well, I'll try leaving the MC tied over night. Also have a friend who is going to give me a hand Tuesday arvo. Still have to change the clutch and brake rotors before the trackday on Saturday... It's gonna be tight!

[Wattie]

Have you tried tying the lever back to the bar and leaving it overnight? Not too sure of the technicalities of why it works, but on my F1 it made a big improvement to lever feel.

It leaves the MC open for any bubbles to travel back to the resivoir... well that what I got told many years ago mind you I dont think it works for radial MC's

it does,

when you have the lever tied, you jiggle the lines, tap them heaps. then leave overnight, the little bubbles work their way to the top. then when you let the lever go later the excess fluid in the lines shoots back into the resevoir (spelling) taking with it the air that has worked its way to the top over night.

Rob, your confusing the crap outta them with this radial stuff, only difference between radial and conventional is the piston runs "forwards" on the bike, ans the conventional runs sideways. the radial is a more direct feel and less flex do to the piston attached straight to the lever.

i think your are refering to "remote reseviors" as apposed to the big solid resevoirs that are part of the M/c moulding.

[robracer]

Thanks Wattie, as I said I think, & they did not have them 25 years ago when I started pulling apart bikes, so I am more used to the original format & non radial thats all.