No, joining the Harley Owners Group (HOG) is not mandatory if you own more than one Harley-Davidson motorcycle. HOG is an official organization established by Harley-Davidson, which offers various benefits and experiences to Harley-Davidson owners who choose to join. These benefits may include access to exclusive events, group rides, discounts on merchandise, and a sense of community with fellow Harley-Davidson enthusiasts.
Joining HOG is a personal choice and is not directly tied to the number of Harley-Davidson motorcycles you own. Whether you own one or multiple Harley-Davidson motorcycles, you can choose to join HOG if you are interested in the benefits and experiences it offers. It's worth noting that membership in HOG typically involves a fee, so you may want to consider the value of the benefits provided by HOG before deciding to join.