A moped refers to a motorcycle with an engine displacement of less than 48CC (it should be called a moped, and a real moped has a pedal riding device similar to a bicycle, which should not be available in the market). The model HL 100T-5A indicates that the engine is 100CC, which belongs to a motorcycle. It is required to apply for a yellow motor vehicle license and obtain an E or D license before driving. This bell is a brand-name car with poor quality. This kind of car is noisy. If the noise is too loud, there may be something wrong with the engine. The noise of four-stroke scooter mainly comes from valve chain, tensioner, valve rocker arm, camshaft and so on. The specific reason can be checked at the local motorcycle repair office.