My mate has a RS50 and reckons it does 60mph RESTRICTED-any one believe him?!.I have a TZR, and im hitting about 69 mph, derestricted of course.it is QUICK. before i had this bike i had a peogeut streetfight.Very slow, was only gettin about 40. I would recommend a TZR to anyone. I am going to buy a 80cc bor-kit for it, i should be hitting 80mph like my other friend.I would highly recommend buying a used TZR however, as for the first 400 miles, they run very slow, and judder, no matter how good you use the clutch.