FSA TH-870G-RS ACB 45x45 1-1/8 headset bearing

Description

When the steering turns smoothly and without play, the bike feels more confident in every corner. FSA TH-870G-RS ACB 45x45 1-1/8 headset bearing restores calm and precision to the front end.

Main benefits

The sealed ACB design helps keep the headset running smoothly even on long rides in changeable weather. It’s suitable for road, mountain, and gravel bikes where precise tracking matters.

The 45° x 45° contact angles support accurate seating in the cups and stable contact around the entire circumference. This makes it easier to maintain the correct adjustment without annoying clicking under braking.

The bearing dimensions match common headset standards, so replacement is usually quick and without unnecessary surprises. Choosing the correct bearing also protects the contact surfaces and extends the service life of the entire system.

Checking compatibility in the EasyHeadset app will help you choose the right type without time-consuming measuring. In practice, this gives you greater confidence that the bearing will fit your frame and fork precisely.

Technical specifications

The outer diameter of the bearing is 39.0 mm.

The inner diameter of the bearing is 30.2 mm.

The bearing height is 6.5 mm.

The inner and outer contact angle is 45°.

Conclusion

The headset bearing is a small part, but it has a major impact on steering feel and the quiet running of the front end. This model from FSA is built for precise seating and reliable operation across different disciplines.

If you’re dealing with play, roughness, or preventative maintenance, the right bearing type often makes a bigger difference than you might expect. With proven dimensions and angles, it’s a great fit for a well-maintained, carefully adjusted bike.

Key features

• ACB headset bearing
• Contact angles 45° x 45°
• Bearing outer diameter 39.0 mm
• Bearing inner diameter 30.2 mm
• Bearing height 6.5 mm

EAN: 4712977700086