Do I need to replace both upper and lower headset bearings?

Best practice is to replace both simultaneously. The lower 1-1/2" bearing wears faster due to higher impact loads — if replacing only one, start with the lower.

Which headset cups are compatible with this bearing?

The ACB 4545 150 BO is a bearing cartridge — compatibility depends on your headset cup geometry. Confirm dimensions against your headset manufacturer documentation.

Are all 1-1/2" headset bearings the same?

No — the outer diameter and seat angle vary between headset standards (IS, ZS, EC). Always verify the specific bearing dimensions match your headset cups, not just the steerer size.

Enduro Bearings

Enduro Bearing ACB 4545 150 BO - 1-1/2 Black Oxide Coated Angular Contact Headset Bearing

Name: Enduro Bearing ACB 4545 150 BO - 1-1/2 Black Oxide Coated Angular Contact Headset Bearing
Brand: Enduro Bearings
SKU: ACB-4545 150-BOX
Price: 2099.00 INR
Availability: InStock
Author: InstaSport Editorial

₹2099.00

Description

ACB 4545 150 BO - 1-1/2" Black Oxide Angular Contact Headset bearing (34mm x 52mm x 7mm: 45x45 deg) Angular-contact headset bearing featuring anti-corrosion Black oxide/Magnetite coated 52100 High-Carbon Chromium alloy races paired with grade 10 Balls. Black Oxide coating provides an extra level of