Yep that's what I was anticipateing, I'm only talking about flat out top speeed increase not cruising speed rpm, that's another story. It will need to be geared up to get the rpm back down to for normal driving. When I had the knobbies on it I could not reach anywhere near redline at full throttle in 6th gear, I would attribute it to spinning mass and roll resistence, my old rear tire which is a D 908 is a full 6 lbs. heavier than the the SM set up and a knobby doesn't roll like a smooth skinned radial. You're about right on 20mph off guess, before I recalibrated the speedo for 17" tires the top speed (indicated) read out was 144 and yes that's mph not kpm.
