Bleeding front brakes

I did a search and found nothing pertaining to my problem. I am working on an 82 GPZ 750 front brakes using a Suzuki master cylinder. I am not using the splitter I am using two braided lines on the the banjo bolt to the M/C.
I rebuilt my master cyclinder and calipers after repainting them and now I can't seem to get them bled properly. I have tried every trick I know and still nothing, 7 hours and about 1 gallon of fluid. Here is what I have done so far.

1. Bled the master cylinder seperate from the system.
2. Gravity method.
3. Vacumn pump from the calipers.
4. Pushed brake fluid from master cylinder to calipers with air pressure.
5. Old school method of pumping the lever holding it in then open bleeder valve, repeat about a thousand times.

To be sure I do not have a problem with the M/C or calipers I seperated each caliper and bled it by itself then then leaving the other caliper disconnected I hooked it back up to the M/C. I get a good firm brake. Each caliper works fine on it's own with the existing M/C. When I hook the calipers back together no brakes or getting it bled. I have working on bikes for over 40 years and have bled hundreds of brakes on motorcycles but this one is very frustrating.
Any ideas would be appreciated.

You could test the master by blocking off the outlet port, with a bolt the correct size/ thread. You still do the pump, hold bleed by cracking the bolt, the fluid should pass the threads, but a bit slower than a bleeder screw. If it pumps up, it'll be like a rock, and doesn't lose pressure or stroke on each pump, then the Master should be good.

why did you change to a different master cylinder? i know if its the wrong size it wont work right, maybe that is some of your problem. when i bleed mine i bleed the left caliper first and then the right side. i used a vacuum bleeder with no problems.

baldy110 wrote: I did a search and found nothing pertaining to my problem. I am working on an 82 GPZ 750 front brakes using a Suzuki master cylinder. I am not using the splitter I am using two braided lines on the the banjo bolt to the M/C.
I rebuilt my master cyclinder and calipers after repainting them and now I can't seem to get them bled properly. I have tried every trick I know and still nothing, 7 hours and about 1 gallon of fluid. Here is what I have done so far.

1. Bled the master cylinder seperate from the system.
2. Gravity method.
3. Vacumn pump from the calipers.
4. Pushed brake fluid from master cylinder to calipers with air pressure.
5. Old school method of pumping the lever holding it in then open bleeder valve, repeat about a thousand times.

To be sure I do not have a problem with the M/C or calipers I seperated each caliper and bled it by itself then then leaving the other caliper disconnected I hooked it back up to the M/C. I get a good firm brake. Each caliper works fine on it's own with the existing M/C. When I hook the calipers back together no brakes or getting it bled. I have working on bikes for over 40 years and have bled hundreds of brakes on motorcycles but this one is very frustrating.
Any ideas would be appreciated.

Already bled the M/C several timesit works fine. This was the M/C that was on the bike when I bought. A P/O had club raced it and the M/C is a litle bigger for a lighter touch on the brakes. An inexpensive upgrade, It worked great before I tore into it all.

Could try this, take the brake pads out of each caliper. Get a block of wood to limit the piston travel so it comes out about 3/4 stroke on each. Then Loosen the bleeder and push the piston back in, letting air/ fluid out. Same for both sides. Keeping bleeder straight up as highest point.

Thanks Motor Head but already tried that one too.

How long do you let it set between bleeding? Is it on its center or side stand? Whats the orientation of the junction Tee is it?
I know I've had some small air bubbles come back up to the masters return port, having the bike on the side stand and the bars turned so the lever is up hill from the hose end. Barely pumping, just enough to cover then uncover the return port.

Im sure I saw a novel way of using a vacumn cleaner and a large glass jar with some tubing.
I'll see if I can find it.

Got it! This is for a car but you get the idea.
forums.acuralegend.org/brake-flushing-bl...e159a84058c23909& ;

and here...but read the comment underneath!
bpostwarclassics.runboard.com/t8332

if everything works fine seperately I would be lead to believe its in the connection at the banjo bolt. either air comming in between the mated lines (at the M/C) are you using the stock bolt with 2 seperate fittings?? could be the bolt length are you using the brass washers between all mated surfaces? post a pic of the setup

quick search

here...read the comment...
bpostwarclassics.runboard.com/t8332