Bleeding brakes. HELP!!!!
Posted 05 February 2004 - 03:27 PM
What am I doing wrong? I am about ready to push my bike into the back yard and burn it !!!!
HELP !!!!!! It almost seems that the master cylinder is not drawing in any fluid to replace the lost fluid at the bottom, and yes the reservoir is full.
Thanks for the help.
Posted 05 February 2004 - 03:41 PM
I've always had someone do it with me so I've never used the tube in the can trick.
I'd just leave the reservoir cap off, have my partner apply full pressure to the brake then I'd break the bleed screw loose while my partner continued to apply pressure to the "lever" until it bottomed and HOLD IT THERE.
Then I'd crank the bleed screw back in and instruct him to let off the lever completely then apply pressure again. I never would have them pump the brakes at this point because (if I'm remembering correctly) it kinda aggravates the system by distributing whatever air is already in there (you are bleeding remember)throught the system.
So, only have them put pressure on the lever again holding the pressure. You then break the bleed screw again and they follow through with pressure until the break bottoms again holding it there until you tighten up the bleed screw. Repeat until no more air bubbles come out of the bleed screw.
Also, you want to check everytime after you break the bleed screw to make certain the reservoir is full.
I don't see any reason why this shouldn't work on a bike. Only prob is it takes two people to do it.
Anyone see any flaws in what I'm describing?
On second thought, maybe I have pumped the brakes up before breaking the screw loose. Not trying to confuse matters but maybe it's worth a try not pumping it up.
Other question would be is why were you bleeding them in the first place? Were they spongy already?
Hope this helps.
Eddie
Posted 05 February 2004 - 03:44 PM
Posted 05 February 2004 - 03:50 PM
Believe me, I'm not giving out ADVICE. Just caught you first so thought maybe I could help. Anyway, So if you were to do as I've described and "pretend" that you were feeling resistance with the second pull, when you break the bleeder loose you would not get any air out? I would think that it would be possible to have so much air in there that you have to purge the pure air before you can get any noticable resistance.... maybe needing to pump them up initially to get some resistance and then start with what I'm describing.
I'm gonna go back and read your original post again.
Eddie
Posted 05 February 2004 - 04:01 PM
Posted 05 February 2004 - 04:12 PM
or you have a humdinger of a bubble in it.
take the caliper off the fork. hold the caliper ABOVE the handle bars. then bleed it.
air rises. if you have a bubble, it will come out this way.
Posted 05 February 2004 - 04:13 PM
Posted 05 February 2004 - 04:55 PM
That's why I was wondering if you were experiencing a PROBLEM before you decided to bleed or you were just changing your fluid.
Posted 05 February 2004 - 05:04 PM
Posted 05 February 2004 - 06:48 PM
Posted 05 February 2004 - 07:20 PM
Posted 05 February 2004 - 10:07 PM
Talked to a guy at my local track and he made me aware of the little ajuster screw on the brake levler itself. I have never noticed that little thing. Ajusted it out a little, and now I got the best brakes I ever had
I may be a nOOb and saying something that is very ovious, but if you have not tried it, its worth a shot.
Posted 06 February 2004 - 02:24 AM
Posted 06 February 2004 - 04:02 AM
I usually always end up with a better feeling brake afterwards.
Posted 06 February 2004 - 07:16 AM
Posted 06 February 2004 - 07:28 AM
First off, you need to bleed the master cylinder. Try pumping the brake, holding the lever in. Loosen and tighten the banjo bolt at the TOP of the brake line. You may need to do this several times. It still may not work.
I have gone back and forth, first trying at the master cylinder, then the caliper and back again.
I had a heluva time when I swapped to a stainless steel line on my WR420. I was there FOREVER trying to do this. Out of exasperation, I did the press the fluid in from the bottom approach. I used a turkey baster w/ clear, flexible plastic tubing attached (thoroughly cleaned and flushed W/BRAKE FLUID) to slowly push the fluid up from the bottom at the caliper. This DID work. I still bled from both ends however for the icing on the cake.
Now, UNLESS you went Honda routing, you CANNOT have that stupid Yamaha loop-de-loop at the caliper while futilely attempting to do this. Hell WILL freeze over before you EVER get that bled.
As mentioned, you can hang up the brake rig from the ceiling to let the air float up.
I have done all of this, which DID lead to success.
Posted 06 February 2004 - 07:47 AM
I will rebuild the master and try the reverse fill with a syringe tomorrow. If that doesn't work, maybe there is a 1982 Honda xr250 with a mechanical drum brake in my future.Check the 'bikes for sale' section for the results.
Thanks for the help.








