clintrandall

Thanks Bassound, that sounds like an excellent plan. I'll give it a go. Thanks.

That's a a good point, I'll order another banjo bleed nipple. There probably is enough give in the airbox to squeeze the slightly bigger banjo bolt with bleed nipple in there. I'm still surprised that it's such a pain in the a*** to do.

I bought it off eBay, there were loads on there. I fitted it today on the caliper and it's helped but the braking force is weak. I think the continued presence of air was from a leak in the master cylinder. The rubber around the inlet from the reservoir was perished, I carefully cut some rubber away and sealed it with JB weld. This seems to have improved things, I think I'm now in a position where I just need to bleed better. I've left it overnight with the pedal clamped in the on position. If that doesn't work I will try new pads as they are only 2mm thick. It that fails I'll remove the system and hang it up.

Cheers Dan, that's very helpful. I've just ordered a banjo bolt with a built in bleed nipple that should help do what you described.

Thank you Mr Lineway, that's very kind of you to clear up that little misunderstanding, it's much appreciated.

I'm experiencing the same problem. I'd like to remove the caliper and master cylinder and try Mcman's method. Can I ask how you ensured air didn't return to the system when connecting the hose from the reservoir to the master cylinder?

Thanks Rustybay, this one is certainly frustrating, but I'm determined to get it done. I'll take the whole rear brake system off today and hang it from the reservoir and bleed again. Do you just leave it to gravity or pump the master cylinder?

Thanks guys, I'm a little confused though. lineway, you say hold the caliper at the highest point, but your photo shows it at the lowest point.

Can this be done without breaking the line again to refit it? Seems a lot of work but I'm more than happy to do it if it works. My introduction to working on trials bikes is proving painful.

I am having a terrible time with the rear brake of my son's bike. It was binding so I removed and clean the pistons, one was stuck solid. I then set about bleeding the system, I removed the master cylinder pushrod and used a crosshead to obtain full strokes. My problem is that it never stops producing air bubbles, I must have put a litre of fluid through. I've tried forcing fluid in the bleed nipple with a syringe until it fills the reservoir. There is still hardly any brake, I then tried to catch any surging bubbles with conventional bleeding from the rear pumping the pedal and it continues to produce air bubbles. I then took the master cylinder apart, the seals look fine. I soaked them on hot soapy water to plump them up a bit and reassembled. Repeating the above bleeding procedure, still loads of air. I'm out of ideas now. Any help would be gratefully received. Cheers Clint