With 1000cc Japanese sport bike levels of torque from the XB9, and lots of high way cruising for my daily commute, plus the supremely careful throttle control required for around the parking lot, I"m surprised I only hear of people going from the XB12 to 9 gearing and not the other way around. I average 45mpg being a hooligan on my 07 XB9SX, but would love if this thing had more top end. I have a deployment coming up and when I get back I'd love to throw a hotter cam and a shorter gear ratio at the XB9 to bring top end power into its life.
I'm assuming it would be as simple as the normal 12 to 9 swap, but in reverse?