This video demonstrates the firing order for the 2009+ Yamaha YZF- R1 (and the YZR-M1) This is the only 4 cylinder engine I know of which uses a crossplane crankshaft, in basic terms it works like one bank of a V8 engine. (edit: I think Suzuki's motoGP bike has a crossplane crank too) The firing order shown here is 1 3 2 4. Up in the video is forward on the motorcycle. For the purposes of comparison to the Yamaha 2008 and earlier R1 the firing interval of the engine shown here is: 1 - 270 degrees - 3 - 180 degrees - 4 - 90 degrees - 2 - 180 degrees - where degrees are crank degrees, and a complete engine cycle is 720 degrees. Unfortunately my tacho and program doesn't go higher than 10,000 RPM.