Dear Acmetack, I have a 49cc scooter that goes up to 40 miles per hour, but I want it to go faster.  What can I do to soup up my moped?

To boost the power of your moped, you can add a sports exhaust to get the speed up to about 50 miles per hour.  If your scooter has a Centrifugal clutch, you can also remove the restrictors of the Variator.  In addition, there is a washer/cone in the exhaust which restricts the exhaust gas flow from the engine.  If you replace this with an aftermarket model, you should see some additional performance.  Lastly, this is getting pretty advanced, but you can change out the barrel head and piston for a bigger capacity one.

You can also check the air filter and see if you can replace it with one that would give you better air flow.  Good luck!