Headset Bearing Enduro ACB 6805 CC BO 1" 27.15×38×6.5 mm (36×45°)

Headset Bearing Enduro ACB 6805 CC BO 1" 27.15×38×6.5 mm (36×45°)

The Enduro ACB 6805 CC BO is a high-quality 1" angular contact headset bearing with dimensions 27.15×38×6.5 mm and 36×45° contact angles. Its races are made from 52100 high-carbon chromium steel and treated with an anti-corrosion Black Oxide coating that ensures long-lasting, worry-free performance.

The Black Oxide process involves multiple chemical baths, producing a 3 μm deep anti-corrosive layer. This treatment also provides a secondary heat-hardening effect, making the material tougher. The races are then super-finished with a mirror-smooth polish for reduced friction and improved rolling precision.

Equipped with large Grade 10 steel balls for even load distribution, the bearing minimizes wear and maximizes service life. Dual-lip seals running in a labyrinth micro-groove protect against moisture and contamination. It is factory-filled to 90% with Almagard 3752 high-pressure grease for superior protection against sweat and the elements.

The Angular Contact (A/C) design ensures all balls are evenly engaged to distribute forces over a larger area, increasing stiffness and durability under braking, cornering, and everyday riding loads.

• Type: Angular Contact headset bearing (ACB)
• Dimensions: 27.15 × 38 × 6.5 mm
• Contact angles: 36° × 45°
• Material: 52100 chromium steel with Black Oxide coating
• Balls: Grade 10, oversized for strength
• Seals: Dual-lip labyrinth micro-groove
• Grease: Almagard 3752, 90% fill
• Use: For 1” standard headset assemblies

Equivalent industry part numbers:

• HD 1320K
• 428420
• TH-373
• MR055
• BAA1159
• MH-P09K

The Enduro Black Oxide line begins with BO-treated chromium steel and progresses to 440C stainless steel. Both share the same labyrinth dual-lip seals, super-finish polishing, and Almagard 3752 grease, offering smooth rolling, maximum durability, and long maintenance-free operation in any condition.