Bike wheels: front, rear or wheelset

Front wheel, rear wheel or wheelset: what should you replace?

The rear wheel carries most of your weight and takes the drivetrain: it is the one that wears and gets damaged most often. The front wheel is simpler, with a hub without sprockets, sometimes fitted with a dynamo that powers the lights on touring and city bikes. A wheelset makes sense when both rims are worn or when you want a real change in how the bike rides: lighter, stiffer or tubeless-ready wheels.

The page also includes freewheels. Despite the name, these are not complete wheels but sprocket blocks that screw onto a threaded hub, a common solution on 5 to 7-speed bikes, kids' bikes and single-speed bikes.

What bike wheel size do you need: how to read the diameter

The reliable reference is the rim diameter at the tyre bead seat, in millimetres, defined by the ETRTO standard. It appears on the tyre sidewall, for example 37-622, and often on the rim, as 19-622 or 622x19: 622 mm in diameter, 19 mm internal width.

• 622 mm: the 700c or 28-inch wheel on road, touring and city bikes, also called 29-inch on mountain bikes.
• 584 mm: 650B, called 27.5-inch on mountain bikes.
• 559 mm: the 26-inch size of older mountain bikes and many leisure bikes.
• 507 and 406 mm: the 24 and 20-inch sizes of kids' bikes, folding bikes and BMX.

A 700c road wheel and a 29-inch MTB wheel therefore share the same diameter: it is the rim width, the axle and the brake that set them apart.

Axle, brake and sprockets: the compatibility points to check

On the axle side, a quick release passes through a 9 mm hollow axle; at the front, the hub measures 100 mm between the locknuts, at the rear 130 mm on most rim-brake road bikes and 135 mm on mountain bikes and city bikes. A solid axle with nuts is found on simpler bikes. The stiffer thru-axle comes in 12x100 and 12x142 mm on road and gravel bikes, in 15x100 and 12x142 mm on mountain bikes, and in 15x110 and 12x148 mm for the Boost standard.

On the brake side, a wheel for rim brakes has a machined braking surface on the rim. A wheel for disc brakes takes the rotor on its hub, either with six bolts or with the Center Lock standard, a splined interface designed by Shimano. Some rear hubs have a built-in brake: a drum brake or a coaster brake, applied by pedalling backwards.

On the sprocket side, at the rear, a cassette slides onto a freehub body whose standard must match: Shimano HG for 8 to 11-speed, Shimano Micro Spline for 12-speed MTB, SRAM XD on MTB and XDR on the road, which is 1.85 mm longer. Other rear wheels take a Shimano Nexus hub, which houses all the gears inside the hub.

E-bike rear wheels: what changes

If your e-bike has a mid-drive motor, the rear wheel is a conventional wheel, but under more stress: choose a double-wall rim with eyelets, a higher spoke count and a maximum load suited to the weight of the loaded bike. Some models are identified for this use, such as the Mavic E-Accès or the Velox Kargo designed for cargo bikes. If the motor is housed in the rear hub, the wheel is not a standard part: the rim is rebuilt around the existing motor, a job for a workshop.

How do you know when a bike wheel needs replacing?

A rim worn hollow by brake pads, whose wear indicator has disappeared, cannot be repaired. The same goes for a crack around the spoke holes, a rim bent after an impact or a hub that turns roughly and develops play despite adjustment. A slight buckle, on the other hand, can often be trued by adjusting spoke tension. Before you order, note the diameter, axle, brake type and freehub body of the wheel you are replacing, and keep your cassette if it is in good condition.

Road wheels, MTB wheels and wheel parts

For a selection by discipline, road bike wheels cover rim depth and the choice between carbon and aluminium, MTB wheels cover Boost standards and internal width, and BMX wheels the diameters specific to the discipline. A new wheel is usually supplied without a tyre: choose one from our bike tyres, with an inner tube with the right valve. To refurbish an existing wheel, rims are also sold separately.

Which bike wheel brands to choose?

Velox, a French maker of bike parts based in La Guerche-de-Bretagne, builds wheels on Mach1 rims, produced near Saint-Étienne, and Shimano or Miche hubs, from city wheels to the Trucky designed for electric cargo bikes.

Rodi, a Portuguese maker of aluminium rims and wheels based in Aveiro, offers the Freeway for city and hybrid bikes, the Parallex in 24-inch and the Blackrock 23 in 29-inch with a thru-axle.

Kellys, a Slovak bike brand founded by the Divinec brothers, offers replacement wheels such as the Draft, in a dynamo version at the front, and the Wasper for V-brakes.

Shimano covers everyday replacement as well as upgrades: WH-RS100 for rim-brake road bikes, WH-MT500 for Center Lock disc-brake mountain bikes, and Dura-Ace carbon wheels for racing.

Mavic, the French wheel specialist based in Annecy, organises its ranges by discipline: Crossride and Crossmax for MTB, Deemax for downhill, Allroad for gravel and E-Accès for e-bikes.

Zipp, an American brand in the SRAM group that makes its carbon rims in the United States, is represented here by the tubeless 303 S for the road and the 303 XPLR built for gravel.

Where can you find bike wheels on sale?

End-of-line wheels move to our clearance wheels, and recently arrived references are listed in new arrivals. Black Friday and the winter sales are also good times to replace a tired wheelset.

Frequently asked questions

What is the difference between a 28-inch wheel and a 29-inch wheel?

None in diameter: both are built on a 622 mm rim. The term 28-inch, or 700c, refers to road, city and touring wheels, while 29-inch refers to mountain bike wheels, which are wider and designed for knobbly tyres. Above all, check the axle, the brake and the clearance in the frame.

How do you know whether your rear wheel takes a cassette or a freewheel?

A cassette slides onto a splined body and is held by a lockring: the freehub body is part of the hub. A freewheel screws onto the hub as a single block and contains the mechanism itself. The two are removed with different tools.

Can you fit a disc-brake wheel to a bike with rim brakes?

Only if the frame and fork have calliper mounts. Without them, the wheel could not brake: a rim designed for disc brakes often has no braking surface. If in doubt, stick with the same brake type as the original wheel.

How many spokes for an e-bike or cargo bike wheel?

Reinforced wheels often have 36 spokes, compared with 28 to 32 on a standard road or MTB wheel. More spokes spread the load better and limit buckling. The spoke count is not enough on its own: also check the maximum load stated for the wheel.

How are bike wheels measured?

The simplest way is to read the ETRTO size on the sidewall of the fitted tyre, for example 47-559: the second number gives the rim diameter. Otherwise, the rim sticker or the bike's specification sheet shows it. Measuring with a tape measure is only approximate, as it includes the thickness of the tyre.