+1 to that. Keeping H or V rated tires on that beast would be a necessity. The hard part is re-acquiring those cat-like reflexes and 15/20 vision you had as a young adult...
A 45 HP twin will easily haul you around at extra-legal velocities, but that's not really the point of a nice torquey twin. For Japanese iron, Kaw's Versys 650 at 67 HP, 460 pounds and the lovely Suzuki V-Strom 650 @ 66 horsepower & 470 pounds are tough choices to beat and thoroughly sorted as well. And as always, there's that old workhorse the KLR 650. Cut down a wee bit it's a dandy road mount.