Try the old school method of bleeding instead of using the Vac-pump. We used the vac method on my YZ and my friends CBR with very poor results. Before you go buying expensive parts bleed the system by squeezing the lever and opening the bleeder. Furthermore, try zip-tieing the lever to the grip and let it sit over night, then come back and bleed it in the morning. Having the line under preassure lets all the air settle to the bottom and released all at once, well supposedly at least. Give it a shot.