Before you decide to sell it out and to put it on fire, take time to read the owner's manual :
During cold or damp weather, the engine may fail to start because the high tension
cable is wet and dirty or the outside insulation of the sparking plug coated with
mud. This provides a path for the high tension current from the magneto to leak to
earth and diminishes the intensity of the spark at the plug points.
Clean the affected parts with a dry rag.
Excessive flooding of the carburetter in a cold engine, normal flooding when hot,
or leaving the machine leaning over to the right with the fuel turned on, can all
make the mixture too rich to fire readily and will prevent starting.
Rectify by opening the throttle and air controls fully and rotating the engine
several times as quickly as possible with the kick starter to clear the over-rich
mixture from the cylinder. In an extreme case of over-flooding the fuel should
be turned off as well until after the engine has started.
After clearing as described, close the twist grip and, leaving the air control
full open, make another attempt to start. If unsuccessful, take out the sparking
plug and clean the internal insulation and firing points thoroughly. They may
be wet with unvaporised fuel. Check the point gap and if necessary reset to
0.18 inches (0.45 mm) and rotate the engine several times to clear the combustion
chamber before replacing the plug.
Provided that the trouble is not of a more serious nature necessitating workshop
attention, the engine should start.
Otherwise, you can try to push the bike !