- Jan 16, 2003
My father has an 03 kx 500. It is stone stock. Lately we have been riding on very tight, technical trails. Alot of first gear. And the beast has ran hot twice. Boiling the radiator over. Is there anything he can do to keep his bike from overheating in the slow areas. The bike is virtually new so the antifreeze is what came in it. What antifreeze we have added back is 50/50 mix. And the radiator has been totally clean both times this has happened.