The stock Metzler 240 tire on the rear is known to cause an optimistic speedo deviation of about 3-4%. Simply changing to the Bridgestone Exedra Max 240, a better overall tire for handling and durability, with it's taller aspect ratio, will cure that deviation to near zero. Ultimately, replacing your 150 in front with a 140 Michelin Commander II is recommended), will improve upon the stock geometry and dramatically improve the R3's handling and maneuverability - plus your bike will feel like it weighs about 150 pounds less than it actually is.