Keith Bontrager famously said of bicycle parts: "Strong. Light. Cheap. Pick Two." It's a saying that still completely (and unfortunately) holds true when it comes to road bike wheels, which, once you've got a quality frame, are arguably the best upgrade you can give your steed.
As the means of keeping you rolling, wheels must offer dependable hubs for drive, high stiffness for accurate tracking, be able to hold a tyre at great pressure, provide a surface for consistent braking – and achieve all these aims while being as lightweight as possible.
Upgrading to a wheelset that hits these targets more accurately than what you're currently rolling on can inject some serious new life into a bike, providing an improved ride quality, faster average speeds, greater braking ability or just a lower weight – something that helps in both acceleration and deceleration.
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With thousands of options available, buying new wheels can be a confusing task. This buyer’s guide is to help educate you on what to look for in wheels, the various features and what the common terms mean.
Basic wheel anatomy
- Hub – the wheel spins around the hub that sits at its axis. On the rear wheel, the hub features a freehub mechanism (unless you're riding a fixed-wheel bike), which allows the bike to coast, but drives forward as desired when you stomp on the pedals. The hub contains the axle, which is what attaches the wheel to the bike.
- Spokes – pieces of wire or similar that give distance between the hub and rim. The number of spokes per wheel and the material choice is important.
- Nipples – the spokes thread into a special nut called a nipple. Most wheels can be straightened through adjusting spoke tension via the nipple.
- Rim – sitting on the outside of the wheel, the rim holds the tyre and provides a braking surface for rim-brake equipped bikes.
Riding purpose
Just as road bikes are now increasingly being designated according to their uses (race, endurance, aero, adventure and so on), wheels too fit into similar categories. Knowing what type of rider you are, and what you want out of your wheel upgrade will simplify and narrow your choices.
Rotating weight is felt most when ascending, and so a wheel suited to climbing is usually designed with low weight in mind. Such wheels generally feature a shallow-profile rim and a low spoke count.
Tyre types
Rim material
Wheel diameter
Rim width
Axle sizes
Freehubs and drivetrain compatibility
Braking
Spokes
Factory vs handbuilt wheels
Buying secondhand
- Rims – check for wear of the brake surface, which should be flat and without any concave shape. Look for any sign of chips and then inspect the whole rim for cracks, especially around the spokes.
- Spokes – check that all the spokes are straight and without gouges or scratches. Squeeze the spokes two at a time – all the ones on the right should feel roughly even in tension with each other. Now do the same for the left, which should feel similar. Unevenness is a sign of a bent rim that’s being held in shape by spoke tension.
- Hubs – spin the wheels by holding onto the hub axles. The bearings should spin freely without any drag or notching. Check that the freehub spins, and yet grabs when you rotate it forward. Also, be sure to double check freehub compatibility with your gears (as outlined above).
Road wheel glossary
- Asymmetric rim – as the rear cassette sits on the right side of the hub, the point at which the spokes attach from the rear hub is offset to the left. With this, an assymetric rim is designed to give a more direct path from these offset spokes to the rim – with the desired result being a sturdier and stiffer wheel.
- Axle – the hub spins around the axle, which is attached to the dropouts of the frame and fork. On a road bike, the axle is always hollow and most commonly designed to work with a quick release lever
- Bladed spoke – a flattened spoke that’s designed to cut through the wind with less resistance. Bladed spokes are common in high-end wheels and also serve the purpose of providing an edge for a tool to hold onto – which can allow for high spoke tension to be achieved. Top spoke brands DT Swiss and Sapim both claim that their best bladed spokes are not only their lightest option, but also the strongest and most durable.
- Butted spoke – a process to the spoke that sees the centre of the spoke being made thinner than the outer sections. When done correctly, this is known to encourage spoke flex away from the weak points, therefore leading to improved durability at a lower weight. Double butted means two different thicknesses; triple butted means three thicknesses.
- Cartridge bearing – in this system, bearings are contained in a cartridge that features the ball bearings, inner and outer race as one unit. The outer race is a tight press-fit into the hub shell, while the axle contacts the inner race. These items are considered perishable, where old are taped out and new cartridges pressed in place.
- Centerlock – a Shimano spline system for mounting a brake rotor onto the hub.
- Clincher – the most common type of tyre system on a road bike. Here a bead on the tyre locks with a lip on the rim. Clincher tyres use inner tubes to hold air.
- Cup and cone bearing – the alternative to cartridge bearing hubs is cup and cone. It's most common on entry-level wheels and all those sold by Shimano – these feature loose ball bearings that run on a permanent outer bearing race, with a cone shaped inner race that can be adjusted.
- Disc brake – brake technology proven in mountain biking (and automotive prior to that) that places a thin plate-like braking surface (rotor) at the hub with a caliper that clamps onto it to slow the bike down.
- Dish – the relation of the rim over the hub. On nearly all frame designs, the rim must be perfectly centered over the hub.
- Double wall rim – this refers to the internal cross section of a rim. Where a single wall rim has one layer of material for the spokes connect to and the tyre to sit on, a double wall rim adds an additional level of material separating the two. This additional layer creates a box type section, which greatly aids in rim stiffness and wheel durability.
- Eyelet – a reinforcing ring in the spoke hole of a rim. An eyeleted rim typically allows for greater spoke tension and therefore a more durable wheel. A rim that claims to feature double eyelets will have the eyelets travel through both walls of the rim (see double wall rim).
- Freehub body – the mechanism on the rear wheel that allows a rider to coast or pedal backwards without resistance.
- Hub – sitting at the centre of the wheel is the hub, which contains the axle, bearings, and rear freehub and holds the spokes.
- Machined sidewall – a finishing process after the rim is made, which helps ensure its braking faces are parallel and even.
- Nipple – the nipple is the nut of the spoke. Typically the nipple sits at the rim, though some wheel designs place the nipple at the hub.
- Open-tubular – effectively a type of clincher tyre system. Open tubulars differ slightly in their manufacturing technique, which is generally to a level similar to high-end tubulars.
- Quick release – A tool-free mechanism for attaching a wheel to a bike. It consists of a threaded rod connected to a lever-actuated cam assembly. The rod is slid through a hollow hub axle and a nut on the opposing side allows tension adjustment.
- Radial lacing – where the spoke leaves the hub and meets the rim in a straight line. This is the easiest form of wheel building and results in the shortest length (lightest weight) spoke possible. This style is popular for front wheels, but does not resist torque appropriately for use on the driveside of a rear wheel or with disc brakes.
- Rim – the outward hoop of the wheel that holds the tyre and acts as a braking surface for rim brakes.
- Rim tape (AKA rim strip) – protective tape used to cover the multiple spoke holes in a rim. Without this, an inner tube would expand through the rim holes and puncture. Some top wheelsets from Shimano, Fulcrum, Mavic and others do not require rim tape.
- Sealed bearing – another name for cartridge bearing.
- Sleeve join – a method by which an alloy rim is joined to form a circle. Sleeve joins are a form of rivet; they are cheaper to produce than a welded join.
- Spoke – bars or wire rods that connect the hub to the rim. They can be made from steel, stainless steel (most common), titanium, aluminium or carbon fibre.
- Spoke flange – the section of the hub for which the spokes attach.
- Spoke gauge – this refers to the thickness of the spoke. Most common is ‘14G’, which commonly equates to a 2mm diameter, ‘15G’ is thinner at 1.8mm. Therefore, ‘straight gauge spokes’ feature a single diameter, whereas the most common double-butted spokes with a 2/1.8/2mm diameter across the length are sometimes referred to as ‘14/15G’.
- Three-cross – this refers to the lacing pattern of the spokes – where each spoke crosses past another three times. This pattern is most common on 32- or higher spoked wheels.
- Thru-axle – a large axle that slides through closed frame dropouts and the hub for a stiffer and more secure wheel connection. Thru-axles are commonly used on mountain bikes (especially higher end ones) but are gradually becoming a more frequent sight on road bikes.
- Trueness – this refers to how straight a rim runs, adjusted via spoke tension (hence the expression to 'true' a wheel).
- Tubeless – an airtight clincher tyre system that uses a tight tyre fit and air pressure to hold the tyre in place. No inner tube is required. This system is backwards compatible with standard clincher tyres and tubes.
- Tubular – a type of tyre, also known as a ‘single’. The inner tube is stitched with the tread, and glued to a concave rim. This is the standard for pro-level racing.
- Tubular glue – a specific glue used to bond a tubular tyre with a tubular rim.
- Tubular tape – a substitute to tubular glue, it’s effectively a double-sided tape that’s cleaner and easier to apply than tubular glue – although many argue not as good as glue.
- Two-cross – this refers to the lacing pattern of the spokes – where each spoke crosses past another twice. It's most common on wheels with 20-28 spoke counts.
- Valve hole – a hole in the rim for the tube’s/tubular/tubeless valve to fit through.
- Wear indicator – grooves or small holes on a rim’s braking surface to show rim condition. When the grooves or holes become flush with the rest of the rim, replacement is advised.
- Welded join – a method by which an alloy rim is joined to form a circle. Welded rims are typically more expensive than sleeve joins as this method results in a stronger and lighter connection.
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