happy bleeding most brakes and fitted new seals to a set of oro biancos today however when creating a vacuum on the lever end to bleed the lever and close off i am getting constant air bubbles and its driving me crackers.
any thoughts?
i am guessing there is air entering the system somewhere but have you any experience?
First place i'd suspect is the O-ring on the bleed syringe, they go baggy in no time, and squeeze out when tightened. We've replaced ours with one from an Avid bleed port screw (have to do it regularly to the Avid bleed kits too).
aye reckon that might be it
The key with most bleed kits is that people tend to over-tighten the bleed adaptors into the bleed ports. This can deform the o-ring and compromise the seal.
Finger tight is enough, if you're still getting a leak try loosening them off slightly. Sometimes this will give a better seal.