Width, yes, but circumference no. 26" x 1.125" will be ETRTO 559; 26 x 1 1/8" will (probably) be ETRTO 571.
@Bearlegged started
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Width, yes, but circumference no.
26" x 1.125" will be ETRTO 559; 26 x 1 1/8" will (probably) be ETRTO 571.