How are your cold starts? Do you need the enricher?
Is the idle adjusted to 900rpms when the motor is hot after a ride?
How many cold starts on each tank? More then a few cold starts and being aggressive on the throttle as Dave mentioned, will destroy your fuel mileage
How long do you leave the enricher on? As JD mentioned, is it possible the enricher is hanging up? Is it possible the l;ittle brass end on the enricher, that has a rubber seal in it needs replacing? There is an oring around the outside, and a flat seal/seat right in the end. If either one of thos are damaged. missing, they will let fuel past.
Double check the float height. Make sure it's no higher then 5mm above the bowl to carb
mating surface on the intake manifold side of the carb.
New needle and seat this year? Last year? Have you run Seafoam, MMO
, or Techron in your fuel lately?
Is it possible something is blocking the needle and seat from closing properly? You can open the bowl drain turn the petcock on and turn the key to on and let the pump(if you have it still) push fuel through the needle and seat to flush it out. About 10 secs will be plenty. Do that when you recheck your float level, and you'll still have the tube on the bowl drain to catch the fuel in something.