Full list of all 84 Lonely Mountains: Downhill achievements.
The base game contains 49 achievements, and there are 5 DLC packs containing 35 achievements.
Cross all finish lines with Trailblazer
Cross all finish lines with Grasshopper
Unlock Mount Riley
Unlock a third bike
Unlock Sierra Rivera
Hit 1 tree and go swimming afterwards
Go swimming 50 times
Hit rocks 1000 times
Hit trees 500 times
Unlock a second bike
Find one resting place
Unlock a night ride
Unlock Redmoor Peaks
Find your first Backer message
Hit 1 tree and 1 rock in one crash
Fall 20 Meters
Jump 15 Meters
Hit 2 trees in one crash
Hit 3 rocks in one crash
Cross your first finish line
Unlock a fourth bike
Unlock a fifth bike
Unlock a sixth bike
Unlock all outfits
Unlock all paint jobs
Complete all challenges on Graterhorn
Complete all challenges on Redmoor Peaks
Complete all challenges on Sierra Rivera
Complete all challenges on Mount Riley
Complete all beginner challenges
Complete all expert challenges
Cross all finish lines on Free Ride
Cross all finish lines on the free night mode
Find all resting places on Graterhorn
Find all resting places on Redmoor Peaks
Find all resting places on Sierra Rivera
Find all resting places on Mount Riley
Crash against a rock, a tree, a cactus and into the water
Ride a trail without crashing
Ride 750 meters without pedaling
Ride 1000 meters without braking
Reach a Top Speed of 100 Km/H or 62 M/h
Cross all finish lines with Pacebraker
Cross all finish lines with Javelin
Cross all finish lines with Boar
Cross all finish lines with Geronimo
Cross all finish lines with all bikes
Hit cactuses 100 times
Find all hidden Backer messages
Cross your first finish line on Eldfjall
Complete all beginner challenges during daytime on Eldfjall
Complete all expert challenges during daytime on Eldfall
Complete all challenges during daytime on Eldfjall
Complete all challenge during night-time on Eldfjall
Find all resting places on Eldfjall
Fall into lava 20 times on Eldfjall
Cross your first finish line on Lostman's Grove
Complete all beginner challenges on Lostman's Grove
Complete all expert challenges on Lostman's Grove
Complete all challenges during daytime on Lostman's Grove
Complete all challenge during night-time on Lostman's Grove
Find all resting places on Lostman's Grove
Cross the finish line of Lostman's Grove with all bikes.
Cross your first finish line on Phantom Heights
Complete all beginner challenges on Phantom Heights
Complete all expert challenges on Phantom Heights
Complete all challenges during daytime on Phantom Heights
Complete all challenge during night-time on Phantom Heights
Find all resting places on Phantom Heights
Cross the finish line of Phantom Heights with all bikes.
Cross your first finish line on Whispering Lake.
Complete all beginner challenges on Whispering Lake.
Complete all expert challenges on Whispering Lake.
Complete all challenges during the daytime on Whispering Lake.
Complete all challenges during night-time on Whispering Lake.
Find all resting places on Whispering Lake.
Cross the finish line of Whispering Lake with all bikes.
Cross your first finish line on Carnelian Cavern.
Complete all beginner challenges on Carnelian Cavern.
Complete all expert challenges on Carnelian Cavern.
Complete all challenges during the daytime on Carnelian Cavern.
Complete all challenges during night-time on Carnelian Cavern.
Find all resting places on Carnelian Cavern.
Cross the finish line of Carnelian Cavern with all bikes.