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Bike handlebar clamp diameter 31.8 mm (oversize)

What is a 31.8 mm handlebar? · Modern device · basis: Sheldon Brown handlebar crib sheet (widely cited reference)

Also called: 31.8 handlebar, 31.8mm handlebar clamp, handlebar diameter, manillar 31,8 mm, guidão 31,8 mm, Lenker 31,8 mm, cintre 31,8 mm

Exact dimensions. True size, with no printing tolerance added.

length
100.0 mm
width
31.8 mm
height
31.8 mm

Notes

  • Clamp (centre) diameter 31.8 mm. Grip area: 22.2 mm on upright/MTB bars, 23.8 mm on drop bars.
  • The file is a 100 mm length of bar at the clamp diameter.

Bike handlebar clamp diameter 31.8 mm size chart

dimensionvalue
clamp diameter31.8 mm (1.25 in)
upright grip area22.2 mm
drop-bar grip area23.8 mm

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Sheldon BrownHandlebar dimensionswebPublisher's page; dimensions are facts

Free files

★ Free files 1 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

bar-31.8mm-100Ø31.8 × 100 mm bar sectionSTEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=bike-handlebar-clamp-31-8-mm

Bike handlebar clamp diameter 31.8 mm (oversize), isometric render of a generated part
Render of bar-31.8mm-100 from the free STEP; not to scale.

Fits with

Bicycle handlebar diameters: 22.2, 23.8, 25.4, 26.0, 31.8 and 35.0 mm, isometric render of a generated part
Bicycle handlebar diameters: 22.2, 23.8, 25.4, 26.0, 31.8 and 35.0 mm8 sizes★ 6 files
Bike handlebar clamp diameter 25.4 mm (1 in, ISO), isometric render of a generated part
Bike handlebar clamp diameter 25.4 mm (1 in, ISO)100.0×25.4×25.4 mm★ 1 file
Bike handlebar clamp diameter 26.0 mm (Italian road), isometric render of a generated part
Bike handlebar clamp diameter 26.0 mm (Italian road)100.0×26.0×26.0 mm★ 1 file
Bike handlebar clamp diameter 22.2 mm (BMX / old MTB), isometric render of a generated part
Bike handlebar clamp diameter 22.2 mm (BMX / old MTB)100.0×22.2×22.2 mm★ 1 file

Questions

What fits a 31.8 mm bar?

Stems, lights and mounts made for a 31.8 mm clamp.