Mountain bike wheels explained
Wheels are an important piece of equipment on your bike, along with tyres they help you to cover all of the terrain that you choose to ride on.
Most mountain bike wheelsets are still made from aluminium; offering a great mix of weight to ride feel but the greatest factors that have emerged in recent years have been wheel size and rim-type.
What wheel size is best for you?
There are now 3 main wheel sizes on the market for MTB wheelsets, the smallest being 26”, the largest 29er’s (700c) and the latest offering and a halfway house between the two – the 650b option.
26 inch wheels
These wheels being small generally offer the lightest option and greatest stiffness at a comparable price point across all the sizes available.
Ride. Being light and stiff the smaller wheel can accelerate up to speed very quickly and with a smaller rotational mass can really tear through twisty single-track at high speed. The greater cornering ability means that pairing with a narrower bar will not sacrifice all the turning capabilities.
27.5 inch wheels (650b)
The 650b is the half-way house between the 26 inch wheel and the 29er. It is designed to offer a great compromise between the two, in terms of weight, handling and speed.
Ride. The 650b has risen to popularity because it retains most of the lightness of the 26" wheels, as well as the snappier handling on twistier trails. However, it also has much of the improved traction and rolling capabilities found in the 29er range. It is quite literally halfway between the two.
29 inch wheels (29er)
Currently the largest wheel option for a mountain bike, the 700c wheel does feel slower to accelerate to top speed as the larger rim and longer spokes increase its weight, hence more effort is required through the pedals to get the wheels spinning.
Ride. The larger contact area that the wheel allows for the tyre to make with the ground provides an increased amount of traction. Paired with the larger circumference of the rim these two features mean that the 29er wheel is more adept to rolling over bumpy ground and creating a smooth riding feeling over small obstacles such as roots and ruts.
Mountain bike rims explained
The second advancement comes in the form of rim type. Standard and tubeless are the two options and again, both give a very different ride ‘feel’.
Designed for use with an inner tube this is the ‘traditional’ way to set up a wheel for riding.
Setup. All that is required is the inner tube itself and rim-tape (if not sealed). The simplicity of design means that an inner tube can be fitted in just a couple of minutes.
Ride. Tyre pressure is an important consideration for the ride feel but generally must be a little higher for a ‘tubed’ setup in order to avoid ‘pinch’ punctures. However, a slightly higher pressure gives a good rolling speed across terrain.
With the advent of tubeless rims this has allowed for the inner tube itself to be removed from the set-up offering a very different riding feel at lower pressures.
Setup. Tubeless requires a few more pieces of kit to achieve the sealed system, tubeless valve and rim tape, sealant and a tubeless ready tyre. But once set up, the bead of the tyre is attached to the wheel and held there, without the use of an inner tube.
Ride. The lack of an inner tube allows the tyre to be run at a lower pressure without the risk of pinch punctures. This gives the feel of much more traction and also great absorbing properties over rough ground. The sealant can also repair small punctures through the tyre even when on the move.