ETRTO and wheel sizes
For a motor wheel the ETRTO number counts, not the inch name. The second number in the marking is the rim diameter in millimetres.
Table of wheel sizes
| ETRTO | Name | Typical bikes | Trap |
|---|---|---|---|
| 622 | 28", 29", 700C | Trekking, city, road, 29er MTB | 28" and 29" are the same rim |
| 635 | 28" × 1 ½ (alt) | Old Dutch bikes | Does not fit 622 kits although both are called “28"” |
| 584 | 27,5", 650B | MTB, gravel | |
| 559 | 26" | Older MTB, touring bikes | |
| 507 | 24" | Youth bikes | |
| 406 | 20" | Folding bikes, cargo bikes | Do not confuse with 451 |
| 451 | 20" (schmal) | Some folding bikes, BMX race | Do not confuse with 406 |
The table comes from our knowledge base. The statement about 635 and 622 is an assumption that is still being checked.