I had similar on a kwak 600 I had. The segments in the commutator were uneven so wore the brushes and covered its self in dust.
Clean it and it was ok for a few weeks then back to like a dead battery.
In the end I chucked it in a lathe an took a very light skim off it to even the segments out. Started fine after that.
There are different hoses for different fluids, and different connectors to suit.
Off the top of my head I cant remember what the differences are with the fittings, but there are differences.
I found this on the Bimota forum, but no dimensions.
"The housing was bored out and a sleeve fitted to suit a smaller piston and seal."
With a bit more digging it looks like the new piston it 28.5mm dia.