Z1OwnersClub GB

Hi can anyone help, put the brakes on my z250 project, all cleaned up new brake caliper seals and covers, new pads, new new cylinder diaphrams, come to fill with oil, pump the levers, wont go hard to allow the bleed nipple to open and draw air off! the pipes are fresh and empty, did not change the pistons could this be why the pressure wont build up or am I missing something ? suggestions please, of a constructive nature, thanks

Top the master cylinder up with brake fluid , then pull the lever in to the bars and using a tie wrap or a bungee hold the lever there .
Then go and do something more constructive until tomorrow , it will bleed up then

If you are using an old master cylinder check for two holes in the bottom of it. If you have two they must both be clear - on the big zeds one hole is a tiny bore and blocks easily.
Use thin guitar string or similar (needle is too thick) to make sure it is not obstructed. Also make sure any new inner seals were fitted correct way round and have not gone wonky as they went in.

Then if still probs prime the master cylinder by pouring fluid and working until it starts to come out with no pipe connected - soon as it does connect the top pipe and wash any stray drops of fluid off.

Repeat with top pipe and brake union connected and have a container to catch fluid. Once it's coming out of the union you can connect up your calipers and hoses (try connecting a side at a time if it won't bleed two calipers at one time) and it should start to build some pressure.

Once you have the whole system connected and primed you should get a few tiny bubbles out of one hole in your master cylinder as you release the brake stroke. That's how air locks can escape and allows excess pressure to be discharged so seals don't blow out (voice of experience here I am afraid!!)
Hope this helps from Mark

Thanks guys, and thanks piggy, levers tied up and trying again tomorrow let time move things on

Problem solved, tied up overnight, no joy, thanks again piggy, used a syringe to suck the oil through, worked a treat

DavidZ1R wrote:Problem solved, tied up overnight, no joy, thanks again piggy, used a syringe to suck the oil through, worked a treat

its the way to do it david ! works every time