^ what he said, I count on 43-45 average for me with some dips into the 30's if constant high speeds and in "perfect" conditions near 50 mpg. Much better after broken in and with the new tune, it's almost exactly what my R1200 gave me.
I've not ridden the "de tuned" version
, but the "A8" motor is a hoot to ride and very manageable on dirt roads/speeds to triple digit cruising, don't dismiss it because the early bikes hadn't been sorted (shame on them, but much better than how Duc and a few others have handled lean tuning, etc.).
Test ride!
