Library › Everyday mounts › Bicycle fork steerer, 1 1/8 in (28.6 mm), threadless

1 1/8 in steerer section Ø28.6 × 100 long, axis on X

1 1/8 in steerer section Ø28.6 × 100 long, axis on X: the outside of the steerer (the wall is not drawn); DXF = the Ø28.6 circle

Exact dimensions. True size, no printing tolerance added. Threads are plain cylinders at the major diameter.

STEP STL DXF free, CC BY 4.0 (credit "Xem Studio")

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From the full sheet

Bicycle fork steerer, 1 1/8 in (28.6 mm), threadless: every size, notes, mating features and sources. What diameter is a 1 1/8 inch steerer tube?