First, its impossible to get an accurate squish clearance across the band without providing initial measurements, so it sounds like he took a guess. The idea in not only to reduce squish, but to cut the head precisely across the band to match the piston dome and maintain that clearance. This is why RBD requires a solder crush sample. As far as compression, again initial data so the final head volume can be adjusted. Basically its done like this: Head milled to bring squish at inside band to spec, band angle cut to even squish across band, head bowl volume adjusted for desired compression.
Compression should be about 200PSI max for pump fuel in a 250. The reason the bikes(all bikes) come set up loose is because as crappy as fuel is here its worse in other places.
Mine runs hard across the range with best gains off the bottom, and is great on gas. Compression is 192 PSI. I'd be interested in what you ended up with.
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