Fuel, spark and compression.
1) pull the air cleaner and manually open the throttle fully while looking down the throat, you should see a good squirt of fuel. If not troubleshoot the fuel system.
2)check for spark @ #1 plug. (I have a cheap spark tester but a phillips screw driver will work or just pull the plug, plug the wire back to it, make sure the metal part of the plug is grounded, turn key on and if you still have the stomp starter, manually engage the starter or have someone do it for you, check for spark. If no spark troubleshoot the ign system.
3) if #'s 1 & 2 pass, makes sire the timing is good and test each cylinders compression. If one or more cyls are low pull the valve cover and troubleshoot accordingly.
Those are quick easy checks that should narrow your problem down to the individual subsystem. Makes it easier to find and repair.
Good luck
Dave
