There's no separate license class in Louisiana for motorcycles. To legally operate a motorcycle here you simply take the test for it and an endorsement is added to whatever class of license you already have.In Louisiana:
Class E ~ "personal driver's license" - regular, everyone has it driver's license
Class D ~ "chauffeur's license" - allows you to drive a cab, limo, schoolbus, etc as well as any vehicle or vehicle/trailer combo under 40' total length, no more than four axles, and under 26,001 lbs. GVRW
Class C, B, and A ~ "CDL" or Commercial Driver's License - required for anything exceeding the above-outlined restrictions. Depending on what specific type of vehicle or combination you're operating will decide which of the three you need.
I have a Class D 'cause I once drove cabs for about three years and it's easier (though more costly) to just renew it as a Class D than revert to a Class E.
I have a motorcycle endorsement, though I do not currently own a motorcycle.