MotoGP 10/11
44 Achievements
PS3
Spick and Span
Win with no penalties, all clean sections, no crashes, no collisions. Not unlockable by Co-riders.
4.1%
How to unlock the Spick and Span achievement in MotoGP 10/11 - Definitive Guide
It is easier to do this in Challenge mode, as you don't get penalties for collisions, and they don't appear to count, like you do in other modes.
Absolutely the easiest way to get this chievo is multiplayer race. Just grab a boosting buddy, switch off the AI, race clean, win ... ding, achievement unlocked.