no spark on a lifan 125cc

[dadof2]

i have just got hold of a liflan 125cc engine with no spark to replace the 125cc engine that has jamed up on one of my kids bikes

the engine ive got still has original oil not yet discoloured it seems to have been at the beach in white sand with very very little use

ive swaped over all electrical from the plug to the coil ,cdi box ,stator plate ,flywheel and all the wiring ive tried disconecting and replacing the kill switch and still have no spark and its got me stumped
i am hoping that ive done somthing wrong that someone else has come across b4 and any help would be greatly appreciated
cheers