Robbie Madison wowed the world by "surfing" Teahupoo on his motorbike. The wave is known as "the heaviest in the world"

Action sports throws up incredible moments on an almost daily basis - the sort of thing that makes your fingers leap instantly to the keyboard to tag in your mates, or type "FAKE" in angry capital letters or just emit a sort of verbal drool of poorly-punctuated incomprehension: "OMG he did wot you got to watch dis WTF?! Looooolhhahaha" Usually followed by a forest of exclamation marks.

"These are the moments that make you emit a verbal drool of poorly-punctuated incomprehension..."

But if that kind of thing is sometimes a bit over the top (we all like to over-react on the internet after all) there are a few moments each year that do genuinely deserve an incredulous reaction. Here are our top 10 from 2015, all of which had our eyes standing out on stalks and our jaws hitting the floor.

And while we'd obviously never advocate the savaging of the English language in the manner suggested above, you'd be forgiven a "WTF?" after watching any of these...

10) Mountain Biker Primoz Ravnik Rides Straight Down a Dam in Slovenia

9) BMXer Jed Milton of Nitro Circus Lands the First Ever Quadruple Backflip on a Bike

8) Surfer Paige Alms Becomes the First Woman Ever to Get Barrelled at Jaws

7) Snowboarder Billy Morgan Lands the World's First Quadruple Cork

6) Motocross Rider Robbie Maddison Surfs "the World's Heaviest Wave" on his Bike

5) BMXer Kris Kyle Makes the World's Minds Boggle With Kaleidoscope

4) Skier Candide Thovex Breaks the Internet (Again!) With One of Those Days 2

3) Mountain Biker Brandon Semenuk Unleashes This Incredible One-Shot Wonder on the World

2) Surfer Mick Fanning Fights Off a Shark Attack Live on TV

1) Mountain Bike Legend Martyn Ashton, Left Paraplegic After an Accident, Gets Back on his Bike

Bonus Last Minute Entry: Surfer Kelly Slater Reveals His Wave Pool Design to the World... And it Looks Incredible

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