Here is the full list of all 10 Psebay achievements.
Drive more than 50m. in the infinite level
Complete all levels of the chapter “Road of Psebay”
Stay underwater for more than 20 seconds (in total)
Create more than 3 levels using level editor
Tear off the front wheel more than 4 times
Fall off the motorcycle more than 50 times
Drive more than 250m. in the infinite level
Get 3 stars at all levels of the chapter “Road of Psebay”
Drive more than 500m. in the infinite level
Drive more than 1000m. in the infinite level