Black Bearing headset bearings are machined and assembled to precise tolerances.

Please check precise measurements against the below to determine the correct size.

SPECIFICATIONS

STEERER DIAMETER: 1-3/8″
OUTER DIAMETER:49mm
INNER DIAMETER: 37mm
HEIGHT:6.5mm
CHAMFER ANGLES:36/45

• Chrome steel balls SAE52100
• Chrome steel races SAE52100
• Premium quality grease
• Also referred to using the following part code: MR031