Here is the full list of all 28 Radial-G : Racing Revolved achievements.
Completed the X-I single player career mode with at least all bronze trophies
Maintain maximum speed in any class ship for 60 seconds or more
Reach player rank level 2 offline
Play the game using a VR headset
Reach player rank level 2 online
Reach player rank level 5 online
Reach player rank level 10 online
Reach player rank level 20 online
Reach player rank level 30 online
Reach player rank level 5 offline
Reach player rank level 10 offline
Reach player rank level 20 offline
Reach player rank level 30 offline
Maintain a winning streak for 5 online races
Hit 5 slowdown gates in a row during a race
Achieve maximum speed in a X-III class ship
Land a jump of over 400m
Travel over 10 MILLION meters
Play the game for a total of over 35 hours
Finish 3 races without hitting another opponent or slowdown gate or fall off the track (any race with slowdown gates of 3 or more laps)
Complete an online race having destroyed 1 other human racers
Complete an online race having destroyed 2 other human racers
Successfully destroy 15 other human racers online
Ram at least 10 other racers out of the way during a single race
Win 3 'Eliminator' races online
Completed the X-II single player career mode with at least all bronze trophies
Completed the X-III single player career mode with at least all bronze trophies
Completed all 3 tiers of all single player career events with all gold trophies