Do Mountain Bike Wheels
Yes, the quality of your mountain bike wheels makes a huge difference in your ride. Having a good set of wheels improves climbing, accelerating, stopping, cornering, and going over obstacles. It also makes your overall ride smoother and safer. The major things to consider when buying bicycle wheels are their strength, stiffness, and weight, which influence the quality of your ride.
Mountain bike wheels are made up of a hub, rim, and spokes. This assembled combination is called the wheelset.
The hub is the middle part of the bicycle wheel. The mountain bike rim is the outer part that attaches to the tire. The spokes connect the rim to the hub. All of these components can be made of different materials and construction, which influence the strength and weight of the mountain bike wheel.
A mountain bike wheel hub is made up of an axle, bearings, and a hub shell. It is often made of steel or aluminum.
The axle of the bicycle wheel attaches to the dropouts in the mountain bike fork and frame using a quick release lever, bolt, or other mechanism.
Bearings- The ball bearings allow the bicycle wheel to rotate smoothly around the axle. They are usually made of steel or ceramic. Higher quality mountain bike wheel hubs have a cartridge system, which means that they are preassembled and the bearings are sealed in a cartridge.
Cheaper bicycle hubs have bearings that are loose and packed in grease, which is sometimes called a cup and cone system. The cartridge bearing system allows the bearings to be more protected from water than the loose bearing system and is very easy to service since it requires simply replacing the cartridge.
Hub Shell- The hub shell connects the bicycle spokes to the hub. There are flanges on each end of the axle that have holes in them for the spokes to attach.
Rear mountain bike hubs have an attachment called the freehub to accommodate the cassette, which is the combination of cogs that make up the rear gears. Hubs also have attachments for disc brakes or are compatible with other types of brake systems.
Rim: Clincher or Tubeless
Mountain bike rims are often made of aluminum alloy, steel, or carbon fiber. Bicycle rims designed for v-brakes or caliper rim brakes have a smooth braking surface and those designed for disc brakes don't need this type of surface.
Mountain bike rims are designed for holding either clincher tires or tubeless tires.
Clincher rims like these
have a bead that attaches to a lip in the rim and an innertube is inflated inside the tire.
Tubeless tire systems are another option that are becoming more popular, in which the tire is sealed to the rim and a tube is not needed. An advantage of tubeless tire systems is you don't have to worry about pinch flats so you can run less air in your tires, which provides better traction and absorbs bumps better.
Universal Standard for Tubeless (UST)
systems are manufactured under certain universal standards. For example, UST tires have thicker sidewalls and beefier beads than tubed tires. There are special rims and tires that are tubeless tire compatible, like the example below, which means you can use them with either tubeless or regular tubes.
There are also special sealants, like
Stan's No Tubes
that you can use to convert your existing tires and rims to a tubeless tire system.
The spokes connect the rim to the hub. Each spoke has a nipple, which is basically a socket that adjusts tension in the spoke. Most spokes are stainless steel, but they can be made of other materials, including aluminum, titanium, and carbon fiber. Nipples are often aluminum or brass.
The term lacing refers to the positioning and pattern of the spokes. For example, a 3 cross lacing pattern would mean that each individual spoke crosses three other spokes.
In the past, more spokes have meant a stronger mountain bike wheel because this means that more of the rim is supported. With advances in rim strength, lacing, and spoke strength that is not necessarily the case, but still debated among some riders.
Mountain bike wheels range in size from 26 inches to 29 inches. 26 inch wheels, or 559 mm wheels, are the most common because this tire size was the first to be used for mountain biking; however, 29 inch wheels are becoming more and more popular.
29 inch wheels, also referred to as 622mm or 700C wheels, came out on the market more recently. These wheels are the same size as typical road bike tires and require a larger bike frame and other components.
Some advantages of 29 inch wheels include improved traction, stability, and momentum. Some disadvantages include issues with fit and slower acceleration. For more information on this, visit the
29er Mountain Bikes: Strengths and Weaknesses page
and then click your back arrow to come back here.
Even more recently, a 27.5 inch mountain bike wheel, or 650B, has come out. This wheel size was designed with the hopes of combining the best of both worlds of 26 inch and 29 inch wheels.
Beefier wheelsets are often desired for freeride and downhill mountain biking. The rims are wider to accommodate wider tires and sustain thrashing. The flanges, which hold the spokes in the hub are often bigger and stronger. There are often more spokes in mountain bike wheels made for very aggressive riding than what you see in cross-country wheels.
Weight and Inertia
When we look at the weight of a wheel, it is important to consider the overall weight, which is what we can feel when we pick up the wheel with our hand.
Another thing to consider is the wheel's rotational inertia, which affects acceleration and braking. This is basically the wheel's resistance to accelerate based on where the weight is in relation to the axle. A lighter rim and heavier axle makes a mountain bike wheel that is quicker to accelerate and slow down than if more of the weight is on the outside of the wheel.
Hand Built vs. Factory Made
Mountain bike wheels can be factory made, hand built in the bike shop or online retailer, or you can build your own wheels. Factory made bicycle wheels are assembled on a machine and fine tuned by humans. Hand built bicycle wheels are built by a mechanic based on your preferences. Building your own wheels involves choosing your own components and putting the wheel together, which requires knowledge and the proper tools.
Each type of bicycle wheel assembly has its advantages and disadvantages. Which type you choose is a matter of preference.
Return to Mountain Bike Parts page
Return to Mountain Bike Buzz home page