Was the plug wet when you took it out? Seemingly no gas? Make sure the gas cap vents, then the fuel is coming out of the petcock. Then get a 3'X3' clean smooth surface and take the carb apart. Remove every jet. Use a non clhorenated carb cleaner and a stiff nylon brush and clean. Get a fine wire and run through the passages, and spray some more. Put it back together, check the float height. Sure hope you got a manual by now? It would be bad news if that bike was made to run 20:1 oil ratio? Its a Husky, rare for here, pretty much a nightmare to get parts, and the only mx model around! Check the reeds, silencer packing and does it have a power valve?