Cycling Mountain Bike Tires

The sizing of mountain bike tires is a bit simpler than that of the touring tires. Mountain bike tires come in two basic sizes, 26” and 29”. These tires are noticeable wider than road tires and even if the diameters were that same, the mountain bike tires will not fit on a road tire rim. 26” and 29” are the two categories and these are further divided according to the tire width. For example 26X1.75, 26X1.9, 26X2.1, and 26X2.2 are some popular sizes.

The larger tire sizes used for extra durability or downhill riding are usually 26X2.3, 26X2.4, or 26X2.6. A wider tire will weigh more, and have more rolling resistance, but have better traction and durability. The width of the tire that you would like to use and the size that you can use will depend on the size that will fit between the forks for your front tire and the chainstay for the rear tire. It is possible that if the rear tire is too wide it can also hit the front derailleurs.

Whereas you want maximum durability from all types of tires, this is an even greater concern for mountain bike tires. Mountain bikes are used in all types of terrain and take a considerable amount of abuse. While road bikes and their tires are designed primarily for speed, mountain bike tires are designed for traction and durability. If the terrain you ride on varies enough, you might consider having a different set of tires for different trails.

If you will be riding primarily on trails with a lot of loose rock and generally rough terrain, you will want to choose a tire that has a lot of traction, that is, a tire that has a good bite to it. These tires will have more obvious pronounced knobs and be wider. As you become a more advanced rider you will find it advantageous to consider front specific and rear specific tires that make it possible for you to navigate a more varied terrain without sacrificing performance.

As a general rule of thumb, the rougher the terrain, then the wider the tire. If you ride mainly on relatively smooth, hard trails then you can use tires that are narrower and smoother. These tires will often be 2.0” wide or less. Mud is the exception to this rule. A wide tire can spell disaster in the mud since they tend to pack the mud between the tire and the forks. A narrow tire with some lugs on the tread works best in these conditions. If you are sure you will be spending a lot of your trip in the mud, then a narrow tire with deep penetrating lugs is a good choice.

Ideally your mountain bike tires would be extremely durable, provide excellent traction, and be lightweight. Unfortunately there must be some trade offs. In addition to the tread design choices, mountain bike tire sidewalls are constructed with either a Kevlar bead or wire bead. The Kevlar beaded designed for performance, are lighter weight, and can be folded for easy storage. If cost is a concern then the wire bead would be the way to go.

Until you gain some mountain biking experience and know which type of terrain you prefer riding on, you should consider some of the all-terrain tires that are on the market. These tires have a low, fairly tightly spaced tread pattern that provide some traction for climbing, but still offers low rolling resistance and some gripping ability on the corners. Take your time to make an informed decision and you will enjoy many miles of carefree biking in the mountains.