Mountain Bike Tire Sizes

A tire size you might see on a road bike.

Mountain bike tire sizes.

Sizes written as decimals such as 2 75 are different than sizes expressed as fractions such as 2 3 4. Sometimes referred to as 650b the 27 5 inch wheel fits right in between the 26 and 29 inch offerings. Whether you are mountain biking on dry trails in utah or through the waterfalls of iceland having the right tires is crucial for the best riding experience. It s actually the same bead seat diameter as 700c tires but most 29 tires are simply too wide and tall to fit 700c wheels.

A cross country bike will have tires in the 1 9 to 2 25 width range. Trail and all mountain bikes will have tires in the 2 25 to 2 4 width range. While 26 inch wheels are still considered the standard for mountain bikes 29 inch wheels are fast on their heels. 29 x 2 3 indicates a tire with a 29 outer diameter and a 2 3 width.

Modern mountain bike tires using this size may be labeled 650b or 27 5. 27 5 also know as 650b or 29 called 29ers with traditional 26 wheels reserved for dirt jump freeride and kids bikes. 700x25c indicates a tire with a 700mm outer diameter and a 25mm width. These sizes can be thought of as a sort of shorthand for decimal sizes each with a corresponding iso measurement.

The sizes you commonly see for mountain bike wheels like 26in 27 5in and 29in all refer to the outside diameter of the wheel with the tire fully inflated. Once you ve identified your tire diameter 29 27 5 or 26 you ll want to dial in your width. Read the size carefully. Most mountain bikes today are offered in one of two wheel sizes.

Tires are essential to mountain biking the type of terrain you ride and they can have a big impact on your riding experience. 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. Mountain bike tire size and width. A hybrid of road and mountain tires cyclocross tires are labeled as 700c and have widths indicated in millimeters like road bikes yet are knobbie like mountain bike tires.

Making a comeback in mountain biking is the 650b. A tire size you might see on a mountain bike. The 29er another popular size for mountain bike wheels and tires. And right behind those big 29ers are wheels of yet another size.

A third type of tire size might appear on either a mountain or a road tire. Conversion tables for common bicycle tire sizes.