try un-doing any changes you made . so if you have good compression and all elctrics and spark seem fine it would lead to some sort of fuel problem .
is it starting if you pop a little fule down the plug hole ? have you tried another carb if you have one ?
is it trying to start or fire ata all or just nothing .. you got kicker and electric or just one ? if electric is there any strange clicking noises from relay
check things like stand cut of switch and bar engine run switch try disable or by pass them .
eliminate one thing at a time and check off what is working fine and should lead to what is causing the problem .
Right so 5 mins after posting that we lost spark I tried kicking it with the ignition off and it sparked Popped the fuel tank on and tried kicking with the key set to off And it fires! Granted its only about 3 revs but it's firing alright!
hmmmmm ignition switch proble then ...they pritty easy to take apart and check the wires ect ... the one im working on now came as no life bike and instantly found 3 broken wires at back of ignition switch ..........