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Front brakes.

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Graeme77:
Had another play today.
I blocked the master cylinder to see if its creating pressure. It seems to be, lever goes solid when its blocked off.
I took the caliper off and bled it with the nipple at the highest point. I bled it from every connection too.

Then i let the piston pump out, filling up the reservoir with fluid as needed, then clamped the piston back in the caliper to back bleed it to the master cylinder.

So, MC seems to be ok, im 99% positive there is no air in the system.
Caliper seems to work properly and doesnt leak.
No other leaks.

But i can still get the lever back to the bars ???
Not as easily as before, but still can.

Ive left the lever clamped to the bars, ill leave it overnight and see what its like tomorrow.

I bodged the piston by filling the pits with JB weld (i know, ill get another). The seal looked good.
If there was any problems with this though it would leak right? Still might when i eventualy get pressure. I want to make sure i can get pressure before i buy a piston.

Only other unknown is the fluid. I had it already. It had been opened before but only a little was used. Lid was replaced nice and tight, been on the shelf for a couple of years i'd guess.

This leaves me with two possibilities i can think of.
1, the fluid is cr*p.
2, the master cylinder seals arent good enough to pressurise the whole system.

Any other thoughts?

Not expecting any revelations here, just talking out loud as it were.

I know these are old bikes, with old brakes, but the lever should go solid right?

Bryanj:
No the lever never went "solid" even when new, as long as the wheel is locked with the lever about 3/4 back thats about it, also old/new fluid can absorb moisture even in a what you thought was a sealed container

Spitfire:
As Bryan has said, always use new fluid, bin the old stuff.

Cheers

Den

Graeme77:
I had left the lever tied back to the bars last night and its a bit better today.

The main news though is i tried the brake levers on a suzuki van van and a honda vrf750 last night and there the same as my cb.

I assumed the lever should go solid, but it doesnt. Even on the vfr and new suzuki i can get the lever back to the bars.

Looks like my front brake is fine.

I need to bleed it agian anyway as the lines arent linked up as i want them, i was too busy trying to get it to work!
So ill get new fluid for the final set up.

Thanks.

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