Enduro Bearings - Enduro Bicycle Stainless Steel Angular Contact Bearing 6806 Abec5 30x42x7mm 22.5g

Angular Conatct Bearings

Enduro produce a line of Angular Contact (A/C) cartridge bearings specifically designed for hubs. In standard radial bearings, only 3 or 4 balls make contact during the load, at any given time. In Angular Contact (A/C) bearings, ALL balls are engaged and spread the force over a larger surface area, to decrease friction and minimize wear. Wheel play can be adjusted out of the hub providing a more stable wheel, and making it easier to adjust disc brakes while still spinning freely.

LLB - Is a double lip seal making light contact, and also rides in a groove making a labrinth seal (reducing friction for less rolling resistance whilst maintaining a good seal, preventing contaminating particles entering the raceways)
Red seal indicates preload side - 5-10 lbs of preload required
Black Seal indicates side to go against frame
15 Degree Contact Angle

Stainless Steel 440C steel balls and raceways

High precision balls are within 5/1,000,000? round. These are military level specification, used for precision equipment. R-64 hardness, of the highest grade.
The ABEC 5 Standard

To meet the ABEC-5 standard, bearing design must pass all tests, which include noise testing at high RPM, extremely close tolerances for I.D. and O.D., roundness of ball, trueness of the races and micro surface finishes of balls and races.
Graphite/Nylon Ball Retainers

Nylon with graphite retainers are virtually frictionless while providing constant lubrication.