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How are you brake lines? With age the rubber lines can break down inside and rubber bits can come off and cause problems as you described. If the lines are old change them along with a master cylinder kit. Don't take shortcuts on breaks! Replacing these parts is routine maintenance.

I'm thinking that a break line may have failed internally and stopping the fluid pressure from releasing, kind of like a one way check valve if that's the case it would be the line from the master to the splitter

i shall check the break lines as well, is it worth upgrading to braded metal, as i have everything dismantled anyway? whats peoples thoughts on that.

Upgrade to braded lines is absolutely the way to go

hal wrote: ↑Wed Nov 15, 2023 5:45 am Upgrade to braded lines is absolutely the way to go

Braided lines are good... as long as you get good braided lines. I installed stainless beaided lines some years ago. The bra9ind on the lines may have been stainless but the connection fittings sure weren't, They rusted like blazes.

Rob

Brake lever not returning is pointing to master cylinder problems, people forget brake fluid absorbs water and then it corrodes steel and alloy, there is a spring in the master cylinder and that too can rot out.

All vehicles should as a rule of thumb fully bleed the brake fluid every 2 years, note endure you use the correct fluid as in specification don't mix DOT4 with DOT5.

well an update on this one, i stripped the breakmaster cyclinder and re-built it up again, had difficulty bleeding them, so i used a syringe to draw the fluid through the system and managed to get some pressure behind the leaver, all is good. except my original problem is still there. no pressure on the first pull, but then pressure is built up, if you leave the break alone the pressure is lost and it needs building agian.

so the next thing to check is one of two thinigs

1) replace the entire master break cylinder
2) replace the break hoses, but i dont understand the logic of the hozes causes the issue i had, i woudl have thought it woudl be slow to reduce pressure not difficult to build pressure.

I’m assuming you have a master cylinder under the gas tank. They tilt upwards at the front and can trap air. Unstrap the hose clamp that attaches it to the frame. Then tilt the back upwards and slowly pump the brakes. You should see bubbles coming out of the holes in the master.

As a final step on my /7, I pull the hand lever in to mid pull and tie it off leaving it that way overnight. This way I believe some of the bubbles have a path to work themselves out. Seems to have helped the past few times.

Kurt

Seth wrote: ↑Wed Dec 27, 2023 8:56 am I’m assuming you have a master cylinder under the gas tank. They tilt upwards at the front and can trap air. Unstrap the hose clamp that attaches it to the frame. Then tilt the back upwards and slowly pump the brakes. You should see bubbles coming out of the holes in the master.

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