Whatever you do, please read Sheldon Brown's page on tire sizing before ordering! Double check the sidewall of your tire to confirm ERTRO sizing in addition to markings of 24x1 or 24x1 & 1/8!
- Etrto: 23-540 / 25-520 (please note that 540 tires are more common on wheel chairs)
- Wire bead
- PSI: 23-540: 110 PSI / 25-520: 90 PSI
- If you put your ear to these tires, you will hear the ghost of Sheldon Brown rumbling:
"If two tires are marked with sizes that are mathematically equal,
but one is expressed as a decimal and the other as a fraction,
these two tires will not be interchangeable."