I designed this for a new fork with a different mount hole diameter. I threw the spare adapter away a long time ago, so I’m sharing this in case it helps someone.

Print Settings

• Layer Height: Use the lowest you can due to fine details; I used 0.1 mm
• Infill: 30%
• Material: Strongly recommend a rubber-like filament such as TENAFLEX; otherwise the flaps may break easily. If flexible filament isn’t available, print horizontally for more rigidity (you’ll likely need supports)
• Supports: Not required (for the standard orientation)

BOM

• 1x M5 screw and 1x M5 nut (works with the original hardware)

Assembly Instructions and Tips

• Minimum fork mounting hole diameter: 19 mm
• The nut pocket is intentionally undersized so it press-fits tightly in TENAFLEX. Just press the nut in.
• If you print with a rigid material, scale down the second half so the flaps grip more tightly. Then snap off any flaps you don’t need.