How to make my bike work on Touch Device?

I want to convert this bike from the standard WASD to work on the Roblox Mobile D-Pad. Does anyone know what the inputs are for each direction?

Cheers,

Michael.

		if Key == "w" then
			Forwards = true
			while Forwards do
				CurrentSpeed = math.min(70, (CurrentSpeed + (Acceleration * (1 / 30))))
				wait(1 / 30)
			end

You would have to use the UserInputService to do that. Here are some resources to get you started: http://wiki.roblox.com/index.php?title=Mobile_Controls