Bicycle Mechanics - tyre size?

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simongrant
12-25-07, 01:53 PM
Hi group,
I currently have 26x1 3/8 tyres on my comfort bike,does this mean all new tyres i put on have to be this same size?

Regards

Simon

operator
12-25-07, 01:59 PM
They can differ in width, but they do need to be 26
Bob Dopolina
12-25-07, 04:50 PM
Hi group,
I currently have 26x1 3/8 tyres on my comfort bike,does this mean all new tyres i put on have to be this same size?

Regards

Simon

Have a look on the tire for and ETRTO size. It will be a 2 digit number followed by a 3 digit number (47-559 or 23-622 for example). The first number is the width of the tire. This you can vary but is limited by the width of the rim (Sheldon's site has a good chart for this). The second number is the Bead Seat Diameter (where the tire hooks onto the rim). This number you must match exactly. No wiggle room here.

rhenning
12-25-07, 04:58 PM
Make sure you look for the ETRTO size as there are two distinct sizes of 26x1 3/8 tires in addition to a 26x1.375 size tire. Bead seat diameters are 590 mm, 597 mm and 599 mms. Roger