Only fill the tank to the first ring at the bottom of the filler neck. Look inside you will see that between the bottom ring and the top ring, there is a vent to the emissions system. Ff you overfill, the excess gas goes down that tube to the emission can that is filled with charcoal and once that gets wet it cuts off the air to the tank causing a lock the gas in the tank wont move without air. This causes sputtering, hesitation and rough running; even quitting.
In the early days, riders with this problem resorted to drilling holes in the gas cap to prevent this vacuum lock, but most found the emissions hose easy to disconnect to relieve the lock and learned to keep the gas level below the ring.
In the early days, riders with this problem resorted to drilling holes in the gas cap to prevent this vacuum lock, but most found the emissions hose easy to disconnect to relieve the lock and learned to keep the gas level below the ring.