The SGM Bearing SB410301570A000 headset bearing is a precision technical component designed for integrated headsets to the 1" 1/8 standard. With its dimensions 30.15 x 41 x 7 mm and 45°/45° contact angles, this angular contact bearing ensures smooth and progressive steering rotation, while withstanding the axial and radial stresses inherent to MTB, road or gravel riding.

Technical Summary

This SGM bearing uses the standardized dimensions of IS41/28.6 integrated headsets, widely used on modern frames. The 45°/45° bevel angles (internal and external) ensure optimal load distribution on the bearing races. The double seals (2RS seals) effectively protect the bearing interior against water, mud and dust, thus extending its lifespan in all weather conditions. Manufactured in SAE52100 chrome steel, both for the rings and balls, it offers industrial-grade hardness and wear resistance.

Technical Highlights

• Universal compatibility: Fits all 1" 1/8 integrated headsets (IS41/28.6), in upper or lower position. Cross references: TK410, TH874, MR062, K345H7.
• High-performance chrome steel: Hardened SAE52100 rings and balls, guaranteeing longevity and low friction.
• Reinforced sealing: Double lip seals (2RS) that effectively repel external contamination, ideal for off-road rides.
• Quality lubrication: Pre-lubricated with high-adhesion NLGI 2 grease with water-repellent properties, minimizing maintenance.
• 45°/45° angles: Provide excellent force distribution and precise steering, even under high lateral load.

Geometry and Standards

The dimensions of 30.15 mm inner diameter, 41 mm outer diameter and 7 mm thickness correspond to the IS41 standard (or ZS44 on some frames). The 45°/45° bevel angle is the most commonly used on modern forks with tapered upper steerer or straight 1" 1/8. This bearing can replace many OEM references: FSA, Ritchey WCS, Cane Creek, Enduro Bearings (ACB 4545 series), TH Industries, etc.

Installation and Maintenance

Installation is carried out using a bearing press or suitable fitting tool (crown-type press), ensuring proper bevel orientation. No specific SGM tooling is required: standard headset pressing tools are sufficient. Thanks to its double seal design, the bearing requires virtually no maintenance in normal use. However, it is recommended to regularly check for play in the headset and clean the outside of the bearing after each muddy ride.

Recommended Use

Suitable for all types of riding: cross-country MTB, enduro, all-mountain, road, gravel and bicycle touring. The quality of materials and SGM design make it an excellent replacement choice to refurbish a worn headset, without going through the often more expensive original part. Demanding cyclists will appreciate the smooth rotation and robustness of this component essential to riding safety and comfort.