3rd Bearing

[krupaG]

My son drives an AR28 with 40 mm axle in Yamaha Jr. Sportmans. What is the theory behind the 3rd bearing? My son's weight is 90 lbs - should that bearing be in or out, thight or loose?

[Caleb White]

im 5'6 and 130lbs. so this may or may not work. we run the yamaha sportsman class with a medium axle and medium hubs. we have the middle bering in but loose on our AR-4. my friend is 5'4 and 115lbs. with med-soft axle, medium hubs with small tyres (fronts on the rear). they have the middle bering off on their AR-4. we are both front runners an our local track.