Have a 04'Sportsman500 50th anniversary. Doesn't have OEM fuel valve. Leaks fuel out of overflow at idle and slow trails. Running distance at 45mph it seems to be starved for fuel. Acted like it was overheating but no light and water is circulating when fan comes on (fan makes some noise like a bearing, but it does draw air). When it shuts down there will be no fuel coming out of overflow for a while, a lot longer than usual and it will not start. Would a carb kit fix? Also bought it used with 28-10-12 front and 28-12-12 rear LTP Mud Lite, are these too big for the engine?