I've had a similar prob with the 6 pot brakes on my TD bike I've still not resolved. I even went so far as to set the whole system individually - plugged the end of the master cylinder: solid at the lever straight away. Master tied into each brake one side at a time - still solid. Both line tied into master cylinder, first 5mm of piston travel is soft but then gets better, without managing to ever feel 'solid' and confindence inspiring.I think a banjo bolt (with a built in bleed nipple) on the master cylinder will help. I've seen the fizzing before when using my Mittyvac and wondered if I was pulling too much vacuum and actually drawing air in past the caliper seals? Good luck - Frank |