Mopeds are an efficient way to get around town, travel to work or ride on the college campus. Mopeds with 50ccs have top speeds of about 30 miles an hour. Although this isn't a problem for most, this speed can make things difficult. If there's a highway on your way to work, for example, or if you have to travel more than 5 miles to your destination, you may want to think about upgrading your moped. With a few modifications, you can make your 30-mile-per-hour moped do 40, or better, depending on the upgrades you make.
Remove the air intake located on your carburettor. It will be a plastic or metal box. Removing this will not harm your engine in any way and could increase your acceleration and top speed by 2 to 3 miles per hour.
Take the spark plug out of your engine and check its spark by running your engine with the plug out. If you can visibly see little "lightning bolts" shooting out of the plug, it is working fine. If you can't see anything, it may be time to purchase a new spark plug.
Consider purchasing a big bore kit online. Specially made for mopeds, these kids replace your stock carburettor and piston with bigger ones. An upgrade like this costs around £195, but you can expect at least 10 additional miles per hour in top speed.
Clean out the muffler and exhaust port on your engine. A plugged-up port can make a moped run slow, as it requires more energy for the engine to work. This can be done by taking a wire brush to the inside of the muffler "can" and port where the muffler connects into the engine.
Thoroughly clean your carburettor. Take it off the engine and remove the insides of the carb, making sure to write down where every screw and bolt go. Then soak the bare-bones carburettor in carburettor cleaning fluid overnight. Then take an air compressor and shoot air through the entire carburettor, making sure to especially work on the tiny gas jets that can easily clog.
If your moped is old, consider replacing the engine's belt. The older a moped gets, the more the rubber on that belt can corrode, causing a loss of power and acceleration. These belts can be purchased from your moped manufacturer's website or on 1977mopeds.com.
If you are uncomfortable working with your moped, consider going to a bike mechanic for help. They know exactly what to work on to get your moped running faster.