Road bike tires generally come in three widths.
Road bike tire sizes.
26x1 26x1 3 4 650c.
Old schwinn cruiser bikes.
Most racers like to use tire 700 width range from 18 to 23 mm to the narrowest alternatives.
Because of the high pressure and desired low rolling resistance road tires come in narrow widths.
25 622 is the international standardization organization iso way of identifying the 700x25c tire in the example above.
These would usually be measured in inches 26 27 etc or millimeters 650 700 etc.
The letter at the end of a tire size is a throwback to an old french system when the letters a b and c designated different inner tire diameters it does not stand for cm.
You see 650b that is same of today s 27 5 inch mountain bike tire and 650c that is little smaller inner diameter instead of the 560b tire and easily got into a few road bikes.
Generally bike tire sizes are indicated with two numbers that correspond roughly to the outside diameter of the tire and the width of the tire.
23c 25c and 28c their width in mm.
Nowadays bike tires are typically marked according to iso standard a system originally developed by etrto european tire and rim technical organization but older english and french tire size dimensions are still used as well use the data from the following tables to determine interchangeability and convert between iso etrto english.
Conversion tables for common bicycle tire sizes.
Despite the relatively consistent size options it s important to know what different tire sizes mean in terms of performance comfort and durability.
Unusual size once used on some gt bikes.
The letter has no use today and can be ignored.
The c is a historic relic from an old french system that indicated the rim sizes using a b c and d.
A tire size you might see on a road bike.
Tire and wheel sizes for road riding don t vary as much as mountain biking with a 700c wheelsize almost universal for road riding and tire sizes typically ranging from 22mm to 28mm.
Some older road bikes still have the 27 inch size.
650c size used for modern high performance road bikes for smaller riders and triathlon bikes.
A common road bike tire size is 700 x 25c meaning the outer diameter is 700 millimeters and the width is 25 millimeters.
700x25c indicates a tire with a 700mm outer diameter and a 25mm width.
When it comes to choosing width there are two major factors at play.
Common road bike widths in millimeters come in sizes ranging from 18 to 23 with a typical road bike tire at 700 x 23.
26x1 1 2 650b 27 5 some raleigh and schwinn mountain bikes french utility and touring bikes some new 27 5 mountain bikes.
This system states the 622mm inner.
Especially any 700 tire nowadays is similar to the size of old 700c tire.
