Start from the Top . Do You have fuel in the tank?
Ensure the Fuel filter isnt clogged or any of the fuel lines are blocked or kinked, and that the fuel isnt too old or contaminated
Have You got a spark at the plug? if not work back to the coil and check for any loose wiring.
Ensure that the air filter is free from debris and clean.
Make sure that the exaust System isnt blocked or obstructed in any way.
I hope this advice helps
Kind Regards Rob.
Rob
May 2011