Can someone help with my moped its not accelerating properly?

when i try to accelerate on the moped it decides not to do it properly and makes a sort of chugging sound, you cant just twist the handle bar you have to constantly keep twisting it back and forth to gain any speed, ive cleaned the fuel filter and the air filter, could it be something to do with the carburetor and will i need to clean it, if so soule someone send me a link to a website where it explains how to do it. Thanks