Despite the popularity of badges in gamification applications, there is a lack of research on how to design badges to increase target behavior. Motivated by this gap, we conduct a large-scale field experiment in a commuting-by-bicycle program to explore efficacies of different badge designs in motivating ridership. We systematically vary the rewards, signifiers, and completion logic components of badges. We find adding an option for sharing a badge on Facebook, as a reward for badge attainment, increases ridership. Changing the badge signifier from a self-interested frame to a pro-environmental frame does not make a difference. Changing completion logic from a fixed to a relative goal increases ridership only among frequent riders. These findings have direct implications for gamification design and provide useful directions for research into the motivations behind the design elements.