New Plug and possible wiring could become an issue as well. check to make sure that you have spark. Take the plug out and crank it over while holding the plug against the cylinder head. It should give you a spark. Make sure of course that you do not hold it with your bare hands, could be shocking experience. Just got the [http://www.keepandshare.com/doc/2797379/1980-suzuki-parts-manual-pdf-may-9-2011-9-53-am-2-3-meg?da=y|parts list] as well as the [http://www.keepandshare.com/doc/2797380/1980-suzuki-fa50-service-manual-pdf-may-9-2011-9-53-am-11-3-meg?da=y|complete service manual] so do feel free to download it. I do hope you get it fixed and let us know about it. Good Luck