CoffeeScript 1 second of request frames (doesn't end gracefully)

gistfile1.coffee

class Game
	loop:0
	started: Date.now();
	start: ->
		window.requestAnimationFrame(this.step())
	step:->
		console.log 'test'
		this.loop += 1
		if (this.started+1000<Date.now())
			console.log this.loop
			window.cancelRequestAnimationFrame()
		this.start()
game = new Game
game.start()