Probably just flooded it. Normally the throttle is closed if you try to start it with the kill wires together in the old set up but this new set up permits you to pull the rope with the throttle open and letting more fuel in whilst the ignition is still off.
It would have been better to install a kill button that remains on unless you hold it down, to avoid this situation being able to occur.
Try and start it another time ( with the switch ON) and if it won't, unscrew the spark plug and see if it is wet with fuel. If so, dry it off with a clean cloth, pull the rope a three or four times to clear the cylinder of excess fuel then refit plug and try again.
Thanks for the reply mate, but the problem is "no spark" the engine is actually in a mini bike.
