Sigutech, that's the Hosi-stuff, isn't it ? They're a pain to bleed properly, so I'm pretty sure it's a bleeding problem. I tried to install my Hosi from my 2006 to my 2012 Adv, and I spent almost 2 days fooling around trying to get it working. Finally I was able to bleed it properly by holding the slave on its side, plunger faced down, and tapping it gently. Thus we were able to get out a very persistant bubble of air, located on the outward end of the plunger shaft. It's a construction hickup, once properly bled these slaves are very reliable...
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