biggun

this may be a silly question but have you checked your air filter? also check your plug to see if there is oil on it. leave the plug out and kick it over and see if your blowing any oil out of the hole. i bought mine in 78 and also had trouble with the ignition electronics box. (the black box) it caused the same thing you are describing. and if you get tired of it and wanna sell it let me know, im lookin for one