Enduro Headset Bearing BO 30.5x41.8x6.5mm 45°/45°
Enduro Headset Bearing BO 30.5x41.8x6.5mm 45°/45°
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SKU: SKU: HB-202600
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🧡 Why Riders buy from us
🧡 Why Riders buy from us
Orders are packed ASAP
Most orders are packed and dispatched within an hour. Submit your order before noon PST on weekdays and it'll ship out the same day!
Genuine quality
We source all our products from reputable brands. Our bearings feature: dual lip seals, full complement MAX bearings for pivots, waterproof marine grease for superb wet weather protection and more!
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✅ Compatible with
✅ Compatible with
This size bearing is also known in the bike Industry by these part numbers:
MR042
870E
MR121
MR070
MR084
MR116
MR155
TH-870E
MH-P08
📦 What's included
📦 What's included
ACB 4545 1125 BO - 1-1/8 Black Oxide Angular Contact Headset bearing (30.5mm x 41.8mm x 6.5mm: 45x45 deg)
Angular-contact headset bearing featuring anti-corrosion Black oxide/Magnetite treated 52100 High-Carbon Chromium alloy races paired with grade 10 Balls. Black Oxide treatment provides an extra level of corrosion resistance and extended worry-free performance
Bearing Features:
- The Black Oxide headset bearings are treated in multiple chemical baths to achieve a 3 micron anti corrosive depth. This process also provides a secondary advantage of heat treatment making them tougher. The BO races then go through a secondary "super grind” polishing the rolling surface mirror smooth.
- Both Stainless and BO bearings are engineered with the largest balls possible, feature dual-lip seals riding in a micro-groove (labyrinth) and are filled 90% with extra high pressure Almagard 3752 grease for the ultimate protection against sweat and the elements. Enduro Angular Contact (A/C) bearings are designed so all balls are evenly engaged to spread the force over a larger surface area, minimizing wear and maximizing life.
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Static load - 980lbf / 4.35kN
Weight - 19.24g
Bearing Dimensions:
- Outside Diameter OD: 41.8mm
- Inside Diameter ID: 30.5mm
- Height H: 6.5mm
- Bearing Race Angles: 45x45deg

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