Bike handlebar clamp diameter 31.8 mm (oversize) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/bike-handlebar-clamp-31-8-mm/  (CC BY 4.0)
Basis: Sheldon Brown handlebar crib sheet (widely cited reference)
Catalog version: 2026-10-20

Overall (mm): length 100.0, width 31.8, height 31.8
- 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.

dimension  value
clamp diameter  31.8 mm (1.25 in)
upright grip area  22.2 mm
drop-bar grip area  23.8 mm

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Sheldon Brown: Handlebar dimensions — web — Publisher's page; dimensions are facts — https://www.sheldonbrown.com/cribsheet-handlebars.html

Free files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/bike-handlebar-clamp-31-8-mm/index.json
API: https://xemstudio.com/api/geometry?object=bike-handlebar-clamp-31-8-mm