BS ISO 5775-2:2021

What is ISO 5775‑2 about?  

ISO 5775‑2 is part two of the multi-series standard on bicycle tyres and rims. 

ISO 5775‑2 specifies tyre fitting relevant geometrical dimensions and designations for straight-side (SS, TSS) type, hooked bead (HB) type and crotchet (C, TC) type bicycle rims. 

Who is ISO 5775‑2 for? 

ISO 5775‑2 on Bicycle rims is useful for: 

• Bicycle manufacturers 
• Bicycle rims manufacturers and suppliers 
• Bicycle industry 

Why should you use ISO 5775‑2?  

ISO 5775‑2 provides general requirements for rim contour, rim valve hole and rim base protection so that you can manufacture bicycle rims effectively and with precision. 

ISO 5775‑2 gives rim profile, rim diameters and designation and marking for straight-side type rims, tubeless straight-side type rims, hooked bead rims, crotchet type rims and tubeless crotchet type rims.  

What’s changed since the last update?  

BS ISO 5775‑2:2021 is the fourth edition that cancels and replaces the third edition (ISO 5775-2:2015), which has been technically revised. 

The main changes compared to the previous edition are as follows: 

• The normative references clause has been added (Clause 2) 
• New definitions have been added for clarification in Clause 3 
• New requirements have been added for clarification in Clause 4 
• The symbols and abbreviated terms have been revised in Clause 5 
• A new clause on tubeless straight-side type rims, with or without humps has been added (Clause 7) 
• A new clause on tubeless crotchet type rims, with or without humps has been added (Clause 10) 
• Annex A has been simplified to remove redundancies and add precision for rim measurements with new tools