Brake Bleeding - a day wasted until i remembered this...

[purplepeopleeater]

Right, i've spent all day trying to fill up and bleed the brake fluid after stripping the caliper. I remembered this technique off a suzi website and gave it a go after wasting money on that mini-bleeder tosh. Even considered being stung with one of them vacuum things. This bloody well works, thanks fastfitter.

'I let Isaac Newton do the work for me

Change hoses and make sure all banjo connections are tight.

Turn the bars to the left and fill master cylinder and slowly and gently squeeze and release the brake lever. Brake fluid will go down, air will come up. Allow 1/2 minute between squeezes - if you rush it you're just pushing the air back down again.


You'll see air bubbles coming back into the master cylinder as you slowly release the brake lever. Keep topping up as needed of course. When the air bubbles stop, go for a cuppa. When you come back, squeeze and release and you'll see a big bubble that's collected while you've been supping.

Do it again. When no more air comes back the hoses are full - now all that's left is any air in the caliper itself. Bleed in the traditional 'squeeze, open and close nipple, release lever' way.

New front hoses fitted and bled - 30 minutes. Rush it and you'll be there all day.'

[bill14224]

I should have done it exactly as purplepeopleeater describes, but since I'm an impatient American I tried to speed-up the process. (to no avail really)

I squeezed the lever over and over getting nowhere until I took the banjo off the M/C and pumped the lever whilst holding my finger over the hole.  That got fluid coming out of the M/C in a hurry.  Put the banjo bolt back on and resumed bleeding and all was well.  Was it faster?  Roughly 20 minutes, but I would have rather been sipping a cold frosty than cleaning-up brake fluid.

[bigfatcat]

I dun unnerstand why these gs brakes are such a pita !  I've never had such trouble with car brakes (except they're a pita in a different way getting access)

[daliumong]

heres a way to get it even faster

to prime fluid into the new, empty hose, disconnect the caliper, raise the caliper so the hose and the caliper are above the level of the master cylinder. then, open, pump, close... repeat... until the fluid gets all the way to the caliper. no more waiting for the fluid to go down and air to come up or whatevers

then I usually use those one way valves to finish bleeding, Those things are a godsend

[daliumong]

oh and i usually stick a wrench between the pads so they have something to press on in the event that the brakes start to become firm

[BaltimoreGS]

I use the same method we use on cars at work.  Connect a clear length of tubing to the bleeder screw, fill the master cylinder and start pumping away.  When you stop seeing bubbles in the clear hose you are done.  Just make sure you keep the master cylinder full while you are pumping.

-Jessie