Front Master Cylinder

[IMM]

I’m having a problem with the front master cylinder on my FZS 600, ok here we go, i can’t  get pressure so i opted for a new cylinder kit did that still no good! when i fill the chamber then go to bleed the brakes I’m getting air coming up in the master cylinder! i no leeks anywhere and when i pump the bake lever the fluid goes back and forth in the brake bleeding pipe, doing my head in anyone got any ideas/help please?

[Wookee]

Bleeding brakes is often a nightmare. Have you tried using a vacuum kit? Makes life much easier. Also, when you say 'new cylinder kit' what was it? Was it a whole new cylinder, or was it a refurb kit with new seals etc?

[Dead Eye]

Are you closing the nipple when releasing the lever at the master cylinder?

1. Open bleed nipple
2. Pull lever
3. Close bleed nipple
4. Release lever

Repeat as required This has worked for me everytime I've bled brakes and access is fairly easy on the fazer to both hold the lever in one hand and a ring spanner in the other

[IMM]

Done all the above and still no good, i used a new cylinder kit and still no {or lack of} pressure, don’t understand why I’m getting bubbles when i pump the handle in the master cylinder?

[His Dudeness]

You could take out the banjo bolt at the master cylinder and put you thumb against the opening and pump the lever. See if you're getting pressure. If you do have pressure bolt the line back on do the same at the banjo bolt at the caliper. Then bleed it at the calipers. Put rags down though because you'll get brake fluid everywhere. Also it's poisonous so wash you're hands

[Sloth]

Have you tried back-bleeding the system, ie, adding fluid from the caliper up?

Basically, fill a squirting spout style oil can with brake fluid and pump a few times to prime it, then attatch this to the bleed nipple with a length of fuel hose, open the bleed nipple and pump the brake fluid in from the can until the  master cylinder reservoir fills up.

Done this on a single disc machine before and it worked just fine, not sure how you'd go on with a dual disc set up tho, tho I'm sure it can be done.

Hope this helps...

[IMM]

Update i have a smaller master cylinder from a SYM scooter and put it in line {place of my master cylinder} and i was shocked to find it worked the brakes, so i now know it must be the master cylinder that is faulty even after a new cylinder kit, so I’m on the hunt for another master cylinder if anyone has one spare or knows of someone with one for sale?