Bike tyres for every wheel size

How do you read a bike tyre size?

Three marking systems coexist on the sidewall. The ETRTO size, the most reliable, gives first the width, then the rim diameter at the bead seat, in millimetres: a 28-622 tyre is 28 mm wide and fits a 622 mm rim. The French system combines an approximate outside diameter and a letter, such as 700x28C. The inch system gives a diameter and a width, such as 29 x 2.25 or 26 x 1.75.

The most common equivalents:

• 622 mm: 700C, 28-inch, and 29-inch on mountain bikes.
• 584 mm: 650B, or 27.5-inch.
• 571 mm: 650C, on some small road and triathlon bikes.
• 559 mm: 26-inch with a decimal width, from 26 x 1.00 to 26 x 2.125, up to fat bike tyres.
• 507 and 406 mm: 24 and 20-inch with a decimal width, for junior bikes, BMX and many folding bikes.
• 541, 490, 440, 390 and 340 mm: the old French sizes 600A, 550A, 500A, 450A and 400A, still found on kids' bikes and trailers.

Why are two 26-inch tyres not always compatible?

Because the inch designation covers several diameters. A 26 x 1.75 tyre fits a 559 mm rim, whereas a 26 x 1 3/4, the same value on paper, needs a 571 mm rim, and a 26 x 1 3/8 corresponds to 650A, on a 590 mm rim. Remember that a width written as a decimal and a width written as a fraction almost never refer to the same tyre. Only the ETRTO diameter settles it: it must be identical to that of your rim, to the millimetre.

Which width should you choose for your rim and frame?

The width can change, within certain limits. The rim often carries its internal width, for example 19-622 for 19 mm, and each tyre manufacturer publishes the widths compatible with each rim width; the same tyre also comes up a little wider on a wider rim. The frame, fork and mudguards set the other limit: leave a few millimetres of clearance for mud and grit. At equal pressure, a wider tyre rolls with less resistance than a narrow one, because it flattens into a shorter contact patch; it also brings more comfort and grip.

Bead, casing, compound: what sets tyres apart

• The bead: the edge of the tyre is reinforced with a steel wire on so-called wired tyres, or with aramid fibre on folding tyres, which are lighter and can be folded.
• The casing: its fabric is measured in TPI, threads per inch. A high-TPI casing is more supple and lighter, a low-TPI casing more resistant to cuts.
• The compound: a soft compound grips better and wears faster. Many tyres combine several compounds, firmer in the centre for rolling, softer on the shoulders for grip in corners.
• Protection: a breaker belt under the tread stops shards of glass and flints, and reinforced sidewalls resist cuts and pinch flats.

Inner tube or tubeless: which set-up?

A tube-type tyre, often marked TT, remains the simplest set-up and suits every rim. A tubeless-ready tyre is fitted without a tube on a compatible rim, with a specific valve and sealant that seals small punctures as you ride. Less prone to pinch flats, it accepts a lower pressure, appreciated in mountain biking and gravel riding; you can still fit a tube in an emergency. For low-maintenance urban riding, puncture-resistant tyres with a thick belt remain the most widespread solution.

What bike tyre pressure?

The permitted pressure range is printed on the sidewall, in bar and psi. Do not go below the minimum, which exposes the rim to impacts, and never exceed the maximum, nor that of the rim if it is lower. Within that range, adjust the pressure to your weight, the tyre width and the terrain: the wider the tyre, the lower the pressure, and a heavier rider or a loaded bike needs more. A tyre loses air naturally: check it regularly with a pump fitted with a gauge.

Road, MTB and BMX tyres: pages by discipline

To compare tyres for the same discipline, road bike tyres cover widths, compounds and tubeless set-ups for road and gravel, MTB tyres cover tread patterns and casings, and BMX tyres the profiles specific to that discipline. With a new tyre, check the condition of your inner tube; if the rim is worn, a complete bike wheel is easy to replace.

Which bike tyre brands to choose?

Continental produces its BlackChili compound tyres in Korbach, Germany, and covers every use: the puncture-resistant Ride Tour for city and touring, the Grand Prix 5000 for the road, the Double Fighter for tracks and trails.

Hutchinson, a manufacturer that makes its bike tyres in Châlette-sur-Loing, in the Loiret, keeps sizes that have become rare, such as 550A in 37-490, alongside the Top Slick for the road and the Cameleon for MTB.

Schwalbe, the brand of the German company Ralf Bohle, offers the Marathon range for touring, the Big Ben for city and cargo bikes, and the Jumpin' Jack or the Billy Bonkers for BMX and dirt jump.

Michelin, the inventor of the detachable bicycle tyre, equips small bikes with the Diabolo City, mountain bikes with the Country Rock and the Wild AM2, and road bikes with the Dynamic Classic.

Maxxis, the brand of the Taiwanese manufacturer Cheng Shin, offers here the Hookworm, a wide tyre with a grooved tread for BMX and the city, the Rekon for MTB and the Velocita for gravel.

Vittoria, an Italian brand that incorporates graphene into its compounds, offers the Zaffiro for road training, the Terreno for gravel and cyclocross, and the Mezcal for MTB.

Bike tyres on sale: where to look?

End-of-line and older references are gathered in our clearance tyres, and recently listed models in new arrivals. To replace a worn pair before the next puncture, also look out for Black Friday and the winter sales.

Frequently asked questions

How long does a bike tyre last?

Its lifespan depends on weight, terrain, compound and pressure: a soft-compound racing tyre wears much faster than a reinforced touring tyre. Replace it when the tread flattens, when the protective belt or the casing shows through, or when the sidewall cracks with age.

Can you fit a wider tyre than the original one?

Yes, with an identical diameter, if the width stays within the range accepted by the rim and if your frame, fork and mudguards leave enough room. Check that it does not rub anywhere, with the wheel turning, and that the pressure stays within the rim's limits.

What do TR, TS, TT and TLR mean in a tyre's name?

TR and TS refer to the bead, rigid steel or folding aramid. TT, for tube type, indicates a tyre to be fitted with an inner tube, and TLR or tubeless ready a tyre that can also be fitted without a tube, with sealant. These markings combine: a folding tyre can be tubeless ready.

Why does the rear tyre wear faster?

It carries most of the weight and transmits your pedalling effort to the ground, which wears its tread faster than the front's. If you only change one tyre, fit the newer one at the front: it provides grip in corners and under braking.

Do you need specific tyres for an e-bike?

A standard pedal-assist e-bike does not need a particular tyre, but models marked E-25 are tested for e-bikes assisted up to 25 km/h and cope better with the weight and torque of the motor. In the European Union, a speed pedelec, assisted up to 45 km/h, requires tyres approved under the ECE-R75 regulation, often identified by the E-50 marking.