Scooterotica

You could fit a banjo bolt with a bleed nipple.

Meds wrote:You could fit a banjo bolt with a bleed nipple.

That still doesn't answer why air should re-enter just because theres no bleed nipple.

what i meant was when bleeding it ,not after it`s assembled. The bleed nipples in the two Webster in board discs i have, use a spring and plunger that act as a non return valve inside them

Ahhh,I understand now.

another trick that might help you, fill the master cylinder, pull the brake lever all the way in, then cable tie it in that position overnight, the air should gradually rise upwards, has worked for me when nothing else would.

Take wheel off & lay it flat, push fluid up from disk to the master. I use a hidden master where I screw the lid off leaving the inner seal in place which lifts when the air escapes. job done

I had one of those ScootRS ones and a UK made version which had a bigger piston. I fitted a banjo with a bleed nipple and managed to get it bled by laying the wheel flat. I did find that they were both quite spongey and on close inspection it turned out that neither really sat solidly against the circlip leading the piston having to take up the slack before the braking started.