Bikes in Gears of War 2?

The Elder Scrolls V: Shadowrider
Look, you paid about £2.50 for horse armour. Can you really argue that this wouldn't sell?

And finally...

Street Fighter IV: Championship Bike Edition
Capcom loves to add a new subtitle to Street Fighter games. This is practically a given.

So there we have it. Adding bikes makes every game better. Fact.