Velocosm or Velocosm Community (both name possible).
Velocosm (the microcosm of cycling) is a social network for all cyclists: commuter, leisure, sports (bicycle racing, mountain biking), bike sharing members, bike travellers, cyclomessenger, city tours by bicycle, police on bike,...
He must bring all these communities of cyclists in a single network.
The logo should be obvious, clear, simple, young, dynamic and be more or less urban bike rather than sports bike.
Try to have a bike or part of it (sprockets, handlebars, spokes, chain). And if there is a bike, it must look on the right.