Honda mopeds are known for their fuel efficiency, portability and toughness. Unfortunately, due to the fact that many Honda mopeds hold a small, 49cc engine, they often cannot exceed 30 mph. This is fantastic for in-town activities, but when you need to go 40 mph or faster, a Honda just can't do it. Luckily, with a little bit of adjustment to the air intake, engine and carburetor, you can make your little Honda moped pretty fast.
Purchase premium high-octane gasoline instead of the regular kind. This boosts the engine's power and makes it run quite a bit smoother.
Replace the air-intake valve in your moped's engine. The more air your engine can get, the better. Get the biggest valve you can purchase for your moped. You can replace this using a wrench and screwdriver, as the valve is usually directly in front of the engine.
Adding a new exhaust pipe can greatly increase your speed and reduce your engine's noise. Purchase the biggest possible exhaust system for your moped. These are available on Honda's website.
If you really want to go faster, purchase a build kit for your specific moped. This kit will include a bigger piston head and a new set of cylinder parts. The kit will require a complete disassembly of your engine, so be sure to purchase a build kit made for your moped.