what tire size and gearing

[6858-400ex]

what size tires do u run at the dunes what gearing

right now i have a stock 400ex ecept hmf k&n jet kit no air box lid and i can run up hills in 3rd but i have 22 in back and 23 in front

[duke416ex]

I had 22 on my 400 for a while, and I would say that 1 down front would be good, it just lugged a lot.