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HELP!!!!!!!! bleeding brakes

Discussion in 'Bling and Appearance' started by cats, Dec 9, 2005.

  1. got dramas .... bleeding front brakes .... ok replaced brake lines... rebuilt calipers .... rebuilt master cylinder..... done all the ususl ... cracked the top hose and bleed that ..... i have an air lock somewhere .... has anyone out there got a pressure bleeder ????????

  2. This is the Gixxer, right?
    Single line to 2-way splitter...
    Pull in and tie the brakelever to the grip with some string/velcro/whatever.
    Have dinner/ watch the news.
    Leave cap off master cyl. undo the tie, ans SLOWLY turn the bars lock to lock (might have to remove some juice out of the master cyl.
    Watch some big, fat bubbles burp...after that, do another quick-bleed, pulling the lever SLOWLY .
  3. You shouldn't need one. The short run of hose usually means an easy bleeding.

    Fill the reservoir and crack open each bleed nipple. Let gravity do the work for a while.

    Refill the reservoir, and slowly apply the brake. When all the way in, close the nipple and release the brake. Refill. Repeat. That should remove all air. If you still have an airlock, then chances are that a seal is passing or leaking, probably in the master cylinder and air is being dragged in, probably as you release the brake. This is when the ports are open to allow fluid to be drawn from the reservoir into the line.
  4. Good advice, but I usually need to leave mine with a rubber band overnight, and then just to be sure, check for any bubbles (blled) out of each caliper in the morning.

    Bleed the brakes as in above post, just be aware that after changing the lines (i.e. empty) this can take a fair while, it took me at least twenty minutes of this for each caliper recently.
  5. ill give that a go .... but the master cylinder has just been reconditioned today .. as the calipers and replaced the lines too .. so everything is new except the caliper housing /mastercylinder housing and i did bleed the top banjo ... bleeding the junction is a drama though as fluid will piss everywhere where u cant catch it /clean it .. ie on inner painter surfaces ... but ill try the gravity idea ... least i can have a drink while its bleeding to death ...lol
  6. Go & buy yourself one of those one man brake bleeding kits -the 1 way valve on a piece of plastic tubing. You can then crack the bleed nipple & pump the fluid out faster than the air will rise back to the top. Works every time for me. Only about $10.
  7. brought one .... all iam sucking through is fluid
  8. What exactly are the symptoms?
  9. wont bleed ..... can pump op the brakes and get about 1/4 leaver . thats it ... and theres no leaks ... everything was replaced today ....... lines .... calipers rebuilt ... master cylinder repuilt ... i got heeps of air out of the calipers and the top banjo ... but iam tippin theres an airlock in the junction ... and if u have used the bleeders u were talking about .. they move fluid about 1/4 inch at a time .and if its locked ....its just going to sit there happy as a pig in poo ... ... cracking the banjos at the junction probably will fix it .. but fluid will wind up all over the bike
  10. well if u have 3 people and a garden hose ... and dont mind laying in brake fluid /water it can b done but i cant morph into 3 people
  11. Jeez how good is this forum? You'd have to PAY for this advice anywhere else; here you've half a dozen people who know exactly what is going on and exactly how to fix things, fantastic!
  12. if i had 1/2 a dozen people ... and especialy one with a power bleeder .. id be laughing ... but i havent .... ive got me .... and no power bleeder
  13. Something doesn't sound quite right. When I have used the 1 man bleeder I seem to get about an inch of fluid movement per lever pull from memory. If the air is in the T junction you should still be able to get it out by bleeding one caliper at a time. The air can't travel down the side that is blocked. You may have to do each side a few times to get it all out. Will take a few reservior refills though :LOL:
  14. well ive given up 4 today .... maybe the brake fairey will fix em over night ... but thanks 4 the help
  15. What does this do, actually? I'm trying to work out what it's trying to achieve.

  16. What it does is to hold stop the brake lever from releasing and sucking air back into the system while the bleeder is open.
  17. well its another day .... so ill try again
  18. well the gravity idea didnt work ..... unless u let it sit for a week i tried it for 4 hours
  19. Yes, I realise THAT. My query was about holding the lever in. All it does is to close off the port from the reservoir and push the piston along its full length of travel to push out any fluid. Sitting there does nothing.

    When the brake lever is at rest, the reservoir is open to the brake circuit, and that's when you use a pressure bleeder to force fluid under pressure into the brake lines.

    I think Cat's has either a problem with one of the reconditioned components where a seal may be letting air in, or that his bleeding technique may still require some refining. Without being there to watch or help it's hard to tell.

    What I found interesting was the idea of turning the handlebars from side to side to make the system "burp". If air is trapped anywhere, I can't see how this would vent it out, particularly as the lines and hoses are all affixed to the fork assembly and all move together.
  20. Squeezing the lever will, hopefully, increase the pressure inside the system enough to shrink the trapped air bubbles to a point where they work out of whatever nook or cranny they're trapped in. After that, gravity takes over and the bubbles, again hopefully, float up the lines to the highest point in the system, the face of the master cylinder.

    Release the master cylinder and the bubbles, hopefully for a third time, float up into the reservoir and out of the hydraulic fluid.

    Yes, but, especially if the bike's on the sidestand, as the bars are turned lock to lock, the angle at which parts of the system sit to the direction of gravity changes, and this might be what's required to set trapped bubbles of air free to float up to the master cylinder where, again, they can vent into the reservoir.