How to choose your MTB wheels?

MTB wheels must be chosen with the greatest care as they play a vital role in the performance of your mountain bike. Note that to make a bike dynamic, you need to save weight on the rotating components. And what is more voluminous and constantly rotating than a pair of wheels? Here is some guidance to help you make your choice.

The standards

• The sizes of MTB wheels for an adult bike: 26"; 27.5"; 27.5+ and 29"
• Rim profiles and materials
• Types of tyre fitting: tubetype (with inner tube) or tubeless
• Spoke pattern types
• Hub types
• Wheel axle types
• Types of MTB brakes: V-brake or disc
• The Boost format

Wheel types

The diameter, the rim, the spokes and the hub are the main elements that will determine the specifications of a pair of wheels.

There are several wheel diameters available on the market. The 26", which was the historical standard diameter, is gradually losing its place with the arrival of new sizes, notably the 27.5" which offers very similar manoeuvrability with better comfort, and the 29" MTB wheel, praised for its excellent rolling capability and speed. As for the 27.5+, it offers better rigidity in terms of the spoke pattern and allows wider tyres to be fitted for better grip on all kinds of terrain.

To choose the right tyre size, you can consult our advice guide: Choosing the right MTB tyres

Regarding the rim, it is worth knowing that the wider it is, the more rigid and resistant it will be against lateral forces. Moreover, a wide rim allows, for the same tyre, a greater air volume that better absorbs rough terrain. And the taller it is, the more rigid and robust it will be against frontal forces. However, it should be noted that this has a direct impact on weight. It is therefore very important to choose a rim whose width and height are suited to your MTB riding. Most often made from aluminium for a good strength-to-weight ratio, you will nonetheless find some carbon models to save weight and improve responsiveness while maintaining a certain level of comfort and good impact resistance. Furthermore, the spoke count is less stressed compared to aluminium wheels, allowing for reduced maintenance. The budget for carbon wheels is starting to decrease; you can find models suited to the discipline from €1,000.

Tubetype or Tubeless? The advantages of fitting tyres Tubeless are undeniable: reduction of pinch flats, the ability to run at lower pressures to increase grip and comfort, a significant reduction in the risk of punctures by perforation with the addition of sealant, or even a significant weight saving in the case of a Tubeless Ready setup. Note that it is always possible to convert a pair of wheels to Tubeless if they are not originally so, thanks to conversion kits.

The spoke pattern ensures a perfect connection between the hub and the rim to transmit power, braking forces and changes of direction; it also tolerates a certain amount of deformation to provide comfort and robustness. The spoke pattern is defined by the number of spokes on a wheel and the type of cross-lacing. The most classic, and still the most reliable today, consists of 32 spokes crossed by 3 (one spoke always crosses 3 others), but to lighten the wheels the number of spokes can be reduced and the lacing type can vary according to the discipline.

The hub contains the ball bearings that allow the wheel to rotate. They can be either of the "cup and cone" type A, requiring more regular maintenance but generally reliable over time; or of the "sealed bearing" type B, maintenance-free (simply replace the bearing when it is defective). This part also provides the interface between the rest of your wheel and the bike according to the axle standard. Some brands offer hubs that are convertible to all (or almost all) standards simply with a set of adapters.

Regarding the wheel axle type, it should be noted that standards have multiplied recently. The choice has therefore become more complex and it is essential to ensure compatibility.

At the front, the most common are the quick-release 9x100 mm axle, or the 15x100 mm thru-axle. There is also the 15x110 mm, called "Boost", used on 27.5+ wheels; the 15x110 mm Predictive Steering, intended only for the Rockshox RS1 fork, and the 20x110 mm.

At the rear, the most common are 9x135 mm or 12x135 mm, 12x142 mm, 12x148 mm (Boost) or 12x150 mm axles.

The choice of a cassette is determined by the freehub body of the wheel; it is therefore necessary to choose the right one to fit your sprockets. We invite you to consult the guide: How to choose your MTB cassette?

Finally, regarding brake mounting, models designed for the V-Brake system are becoming increasingly rare, as it has given way to disc braking, for which two fixing standards exist: Center Lock 1 from Shimano / DT Swiss (or AFS from Fulcrum) and the 6-bolt 2.

What is the Boost format?

The new MTB frame geometries and the use of increasingly wider tyres in 27.5" or 29" have forced manufacturers to develop new standards. As a result, some bike models require axles extended by a few millimetres called "Boost", a format that appeared in 2015.

The front axle thus moves to 15x110 mm A and the rear to 12x148 mm B. The chainline is also different (52 mm instead of 49 mm) C, impacting the dimensions of the cranksets and the offsets of the chainrings.

The advantages:

Superior lateral stiffness on 27.5" and 29" wheels.

More clearance for tyres.

More efficient frame geometries for 29" or 27.5+" (shorter chainstays).

Development of new drivetrains.

It is possible to convert certain pairs of wheels from 12x142 mm at the rear and 15x100 mm at the front to 12x148 mm and 15x110 mm with conversion kits (check compatibility before purchasing).

Which wheels for my riding style?

To achieve the most dynamic setup possible, the ideal is to find the lightest pair of wheels that is strong enough for your MTB riding. The choice of diameter will be determined by the rider's size and also by the frame geometry; for the other characteristics, here is what we recommend:

• Touring
  For touring riding, a classic spoke pattern will be the most reliable. A rim between 20 and 24 mm wide will give you a good compromise between robustness and comfort.

• Cross-Country
  For XC rides, if performance is what you are after, consider carbon wheels, but you will also find very good aluminium wheels with a low spoke count to keep weight down. To prioritise efficiency and lightness, choose a model wider than 24 mm.

• All-Mountain / Enduro
  You can either opt for a classic spoke pattern for reliability, or a slightly reduced one to gain in responsiveness. A rim between 28 and 35 mm will provide all the comfort and resistance needed for this discipline.

• DH / Freeride
  When it comes to DH / Freeride, a classic spoke pattern will be almost mandatory to limit the risk of breakage. All on a rim width of 28 mm and above, for maximum tyre volume.

• E-MTB
  For this discipline, the wheels are specific with a fairly wide rim profile starting from 30 mm and thicker. The spokes are oversized and more robust. The hubs are also more resistant to support the motor torque and higher loads.