Hi so this is not very technical. But I noticed that when I hit the brakes on my 2000 Ducati 900ss. And I’m holding the back brake eventually it washes down and my foot pedal drops and it does not hold my rotor any longer . I even bled the caliper upside down so that I can get the trapped air. So I took off this master cylinder and this is what it all looks like and it seems to me that the seals look well. For the price I might as well just buy a whole new master cylinder but could you guys take a look at the picture because if I can rule this out then I can MoveOn but there’s really not much more to rule out. But the break so many times I know there was no air in that system But the break so many times I know there was no air in that system Thank you
It’s not like there’s fluid leaking anywhere whenever this happens so I’m assuming the fluids getting past the seal in the master cylinder and going back up into the reservoir. If I pump the brakes right after it does this I’m cool again for a little bit but if I try to hold on the break like at a red light that’s on the hill eventually to let go in the pedal go down!
your English is very poor so I'm struggling to work out what you are talking about.. that said, the rear brake on most ducacti are shit. Adapt ya riding style to suit....
Sorry. When I push my rear brake lever it applies the brakes , and works. But after a minute the pedal just dropped and I loose pressure to the caliper pistons and I lose my braking ability. I bled the lines many times. There’s no leaks. Also There’s a trick where you take your caliper and turn it over where your bleed valve is above instead of below sometimes air it’s trapped at the top of the piston in the caliper there’s a trick where you take your caliper and turn it over where your bleed valve is above instead of below sometimes air it’s trapped at the top of the piston in the caliper . Did that no effect. Imagine sitting at a red light on a hill and you’re using your back brake and then all of a sudden the pedal sinks and your bike drifts backwards. Ugh sucks
Sorry man I talking to my phone and it translates I mean I speak English because I’m from Pittsburgh I just hate using my fingers specially cause they’re very greasy lol. Sorry man
Yes I’m just gonna clean it put it back together see what happens. A whole new cylinder is only 50 bucks and the seal kits are like 27 so I mean I might as well just get a whole new cylinder
I've have and have had a few ducati and apart from my 749 none of the rear brakes are worth a wank...
Honestly I just like having my back break because it only takes one set of pads to replace so I try to use it a lot unless I’m cornering etc. or Wheelies. Lol
No I seen no issues with any of the rubbers. Not a single thing. The only thing that I was thinking is the actual rubber seal at the tip of the piston may be worn and isn’t holding itself against the cylinder well anymore. Just to Im a car mechanic as a job. Hobbyist with my motorcycles Hobbyist with my motorcycles Lol. About to put her back on the bike and see
I put everything back and now my brakes don’t work at all the pedal just consistently goes all the way down as far as it can go as opposed to building force. I get confused with this because I think sometimes I get air trapped somewhere and I can’t get it out and try to pump it out and everything I get confused with this because I think sometimes I get air trapped somewhere and I can’t get it out and try to pump it out and everything Ugh. I don’t know why simple brakes systems give me so much problems
I’d just get a new master cylinder for $50, fit, fill, bleed, forget. Too much faffing about with uncertain outcomes otherwise. Interesting you’re dictating to your phone, I always wondered why there were the repetitions of sentences, pretty good speech to text though
The symptoms are definitely caused by fluid leaking past the M/cylinder seals. But as Paul says, it is probably more cost effective to fit a new one.
