Two dealers of Harley-Davidson Japan who are remarkably different in terms of sales performance were selected and analyzed for a case study. It was found that these dealers were very different in their management of customer-to-customer (C2C) interactions. The high-performing dealer put into practice the following aspects, which were not seen with respect to the low-performing dealer: (i) creating groups of customers in their customer community according to “new owner,” “intermediate,” and “advanced” groups; and (ii) sponsoring original events for each group. The customer vehicle replacement rate and sales performance rose not only for C2C interactions within groups for activities (i) and (ii) but also for C2C interactions between groups.