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.
Road bike tire sizes.
Road bike tires generally come in three widths.
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.
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.
This system states the 622mm inner.
Conversion tables for common bicycle tire sizes.
Touring bikes come in many shapes and sizes depending on the intended usage from light and fast tourers based loosely on regular road bikes to round the world heavy duty models.
The letter has no use today and can be ignored.
A third type of tire size might appear on either a mountain or a road tire.
25 622 is the international standardization organization iso way of identifying the 700x25c tire in the example above.
The c is a historic relic from an old french system that indicated the rim sizes using a b c and d.
Because of the high pressure and desired low rolling resistance road tires come in narrow widths.
Tyre size typically varies from 25mm to 42mm and some heavier duty touring bikes use 26 inch mountain bike wheels with even bigger volume tyres.
Common road bike widths in millimeters come in sizes ranging from 18 to 23 with a typical road bike tire at 700 x 23.
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.
Especially any 700 tire nowadays is similar to the size of old 700c tire.
Despite the relatively consistent size options it s important to know what different tire sizes mean in terms of performance comfort and durability.
700x25c indicates a tire with a 700mm outer diameter and a 25mm width.
23c 25c and 28c their width in mm.
26x1 26x1 3 4 650c.
A common road bike tire size is 700 x 25c meaning the outer diameter is 700 millimeters and the width is 25 millimeters.
A tire size you might see on a road bike.
650c size used for modern high performance road bikes for smaller riders and triathlon bikes.
26x1 1 2 650b 27 5 some raleigh and schwinn mountain bikes french utility and touring bikes some new 27 5 mountain bikes.
When it comes to choosing width there are two major factors at play.
Old schwinn cruiser bikes.
Unusual size once used on some gt bikes.