This study examines the governance of e-bike mobility in Nanjing, China, through ethnographic fieldwork combining in-depth interviews, participant observation, and mobile video documentation. Drawing on the politics of mobility, urban informality theory, and critical governance scholarship, it argues that e-bike mobility in China occupies a quasi-informal gray zone, a structural condition between legality and illegality that the state continuously reproduces rather than resolves. Successive revisions of national technical standards have failed to formalize e-bike practices because they target embodied, relationally embedded modes of movement as though they were discrete technical parameters. The study demonstrates that the resulting regulatory ambiguity functions not as a governance failure but as a governance technique, maintaining discretionary enforcement power over a population of permanent micro-violators. Within this space, riders' everyday noncompliance constitutes not deviance but a mode of urban living: an embodied reclamation of mobility and rights to the city.