Originally Posted by
Racing Dan
A wheel that spins freely under the weight of the valve is not preloaded.
My wheel bearings have zero play, NONE, and are therefore preloaded. They are not tight, which would be excessive preload, resulting in an interference fit.
Once spun, my wheels will eventually "pendulum" for a few cycles before they finally come to rest.
Excessive preload can cause increased heat, fatigue, and torque. Insufficient preload can allow resonant vibration causing fretting of the raceways.
Bearing Preload - National Precision Bearing