Headset Cartridge Bearing Cane Creek 40 Series 1-1/8" IS42 30.2x41.8x6.5 mm 36° Inner 45° Outer Black Oxide

Not all IS42 headset bearings are created equal.  Some have 2 45° angles while others have a 36° inner and 45° outer.  Some are 8 mm thick while others are 6.5 mm thick.  Measure your old bearing carefully.