Here is the full list of all 19 Race.a.bit achievements.
Unlock all achievements.
Win bronze medals on all official tracks.
Win gold medals on all official tracks.
Win bronze medals on at least half of the official tracks.
Beat a friend on a track you created.
Challenge a friend.
Race on a hundred community tracks.
Win a bronze medal on at least one official track.
Rate fifty community tracks.
Race on fifty community tracks.
Rate twenty community tracks.
Explode.
Race on ten community tracks.
Rate a community track.
Rank in the top 10 of a highscore list.
Upload ten tracks you created.
Upload twenty tracks you created.
Upload a track you created.
Fall of the edge.