OK, this is NOT a definative Scooter tuning guide, nor does it delve into the best combination of Jets, Rollers or Tyre compounds. There are too many combinations to contemplate, so I'll stick with a nice simple overview of what you really need to know. First, the nasty stuff. Legalities You must be aware that at 16 you are only legally licenced and insured to ride a 30mph Moped, assuming you have a CBT.  That means no go-faster modifications, or you are risking a total loss of licence and when you get it back, prohibitive insurance costs. THE COURTS ARE FULL OF PEOPLE WHO THOUGHT THEY WOULD GET AWAY WITH IT! At age 17 or more, you can ride a 125cc UP TO 14BHP unless you have passed a full motorcycle test. Unrestricted or Tuned Mopeds are fine too, although the 14bhp limit applies (No problem normally) and the machine should have been re-registered. CBT Riders are not allowed to ride tuned (Over 14bhp) machines, or those with Big Bore kits. The penalties can be harsh! A driving ban for 12 months, Huge fines, and worst of all A CRIMINAL RECORD for riding uninsured. This may prevent you doing important things in later ...