Bicycle bottle-cage bosses: M5 × 0.8 on 64 mm — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/bicycle-bottle-cage-bosses/  (CC BY 4.0)
Basis: Wikipedia, Bottle cage: two holes 64 mm (2 1/2 in) apart, threaded for M5 × 0.8; a standard cage holds a 73 mm bottle
Catalog version: 2026-10-20

Sizes: see table below
- Frames carry pairs of threaded bosses (or rivet nuts) for a bottle cage: M5 × 0.8, 64 mm between centres. The same pair is used for pumps, tool kits, accessory cages and many mounts.
- The 64 mm is the published metric figure; 2 1/2 in is 63.5 mm. Slotted cage holes take up the difference; for a part with round holes, check the frame.
- Files: the pattern as a DXF (two Ø5 circles, the M5 major diameter, 64.0 apart) and a template strip 80 × 12 × 3 (my size) with Ø5.5 holes, the ISO 273 medium clearance for M5.
- A standard cage holds a Ø73 mm bottle.

feature  mm  from
boss spacing  64 (2 1/2 in)  Wikipedia, Bottle cage
thread  M5 × 0.8  Wikipedia, Bottle cage
bottle a standard cage holds  Ø73  Wikipedia, Bottle cage
clearance hole drawn  Ø5.5 (M5 medium, ISO 273)  ISO 273

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Wikipedia: Bottle cage: two M5 × 0.8 holes 64 mm apart; standard cage holds a 73 mm bottle — web — CC BY-SA 4.0 (text) [verify license at link] — https://en.wikipedia.org/wiki/Bottle_cage

Free files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/bicycle-bottle-cage-bosses/index.json
API: https://xemstudio.com/api/geometry?object=bicycle-bottle-cage-bosses