A tubular tyre, referred to as a tub in Britain, a sew-up in the US, a single in Australia, or just a tubular is a bicycle tyre that is stitched closed around the

inner tube An inner tube is an inflatable torus that forms the interior of some pneumatic tires. The tube is inflated through a valve stem and fits inside the tire casing. The inflated inner tube provides structural support and suspension, while the out ...

to form a

torus In geometry, a torus (: tori or toruses) is a surface of revolution generated by revolving a circle in three-dimensional space one full revolution about an axis that is coplanarity, coplanar with the circle. The main types of toruses inclu ...

. The combination is then glued (sometimes with two-sided tape) onto a specially designed rim, referred to as a "sprint rim" in Britain, and just a "tubular rim" in the US, of a

bicycle wheel A bicycle wheel is a wheel, most commonly a wire wheel, designed for a bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels. Bicycle wheels are typically designed ...

. The combination of a tubular tyre and its tubular rim is lighter than that of a clincher tyre and clincher rim, and will therefore always result in less rotating mass or a stronger construction. Tubulars can also be used over a wider range of tyre pressures from 1.7 to 14

bar Bar or BAR may refer to: Food and drink * Bar (establishment), selling alcoholic beverages * Candy bar ** Chocolate bar * Protein bar Science and technology * Bar (river morphology), a deposit of sediment * Bar (tropical cyclone), a laye ...

(25 to 200 psi), compared to the typical 6-9 bar on a clincher tyre.

History

For amateur road cycle racing, clincher tyres largely replaced tubular tyres in the early 2000s, but saw a resurgence when carbon rims increased in popularity, as the carbon rim better suited the tubular design. In the 2010s, tubular tyres were still commonly used for indoor

track racing Track racing is a form of motorcycle racing where teams or individuals race opponents around an unpaved oval track. There are differing variants, with each variant racing on a different surface type. The most common variant is Speedway which h ...

(where the closed track makes punctures from

road debris Road debris, a form of road hazard, is debris that accumulates on or off a road. Road debris includes substances, materials, and objects that are foreign to the normal roadway environment. Debris may be produced by vehicular or non-vehicular sour ...

less commonplace), professional

road racing Road racing is a North American term to describe motorsport racing held on a paved road surface. The races can be held on a race track, closed circuit—generally, a purpose-built racing facility—or on a street circuit that uses temporarily c ...

, road

time trials In many racing sports, an athlete (or occasionally a team of athletes) will compete in a time trial (TT) against the clock to secure the fastest time. The format of a time trial can vary, but usually follow a format where each athlete or team set ...

, and cyclo-cross racing. In 2009, a tubeless tubular with an integrated airtight liner instead of a separate inner tube was introduced.

Weight considerations

The tubular tyre and rim combination has the potential to either be slightly lighter or stronger than more common clincher tyres. While the clincher tyres and rims technology has caught up in recent years, the total weight of a tubular rim and tyre is still always lighter than its clincher equivalent. Outside racing, the total lightness advantage is somewhat offset by the need to carry at least one entire spare tubular tyre (only a patch kit or inner tube are needed for clincher tyres). Yet the extra weight—and more importantly, rotational inertia—is off the wheel, and a tubular tyre therefore has the potential to accelerate more easily. Advances in tyre sealant have made carrying an extra tyre a bit outdated.

Safety

Puncture safety

An advantage of tubular tyres is that it is a "closed system" where the inner tube is enclosed within the outer tyre casing, meaning in the event of a flat that the air typically escapes far less quickly than with a clincher. For this reason tubulars are generally regarded as safer to ride than clinchers on fast mountain descents.

Controllability in the event of a puncture

A properly glued tubular tyre may be regarded as safer in the event of a puncture at high speeds because it is not as susceptible to roll off the rim, tubular and tubeless tyres in which punctured tyre more easily can roll off the rim and lead to loss of bike control, and a crash.

Heating from rim brakes

Tubular tyres can be less safe with

rim brake A bicycle brake reduces the speed of a bicycle or prevents the wheels from moving. The two main types are: rim brakes and disc brakes. Drum brakes are less common on bicycles. Most bicycle brake systems consist of three main components: a mecha ...

s on long descents because the heat generated by braking can cause the glue holding the tyre to the rim to fail. Additionally, excessive heat from rim brakes can cause the tyre pressure to increase so much that the tyre can explode, but this problem also applies for clincher tyres used with rim brakes.

Tyre change

When a tubular tyre is worn out, it is easiest and most common to replace the entire tyre. If it punctures and is to be repaired, it requires more labour to repair than a clincher tyres (wired–on in Britain), as the tyre must be removed from the rim, opened up, patched, sewn back up, then finally glued back to the rim. In emergency situations, for example in the event of a flat tyre on a bike ride, one can get home by cycling on a new tubular tyre that has not been glued, or with a previously used one with glue that has not dried completely, but care must be taken to ride gently until home as the tyre will not be fully affixed to the rim. Tubular tyres may have less chance of a puncture when changing tyres compared to clincher tyres where the tube can easily get pinched and punctured. Tubular tyres are typically fitted with

Presta valve The Presta valve (also French valve (FV) or Sclaverand valve) is a type of tire valve commonly found on high pressure bicycle inner tubes and is commonly used on tubeless setups. It consists of an outer valve stem and an inner valve body. A lo ...

Gallery

File:Bicycle rim diagrams 04.png, Rims for tubular tyres, referred to as "sprint rims" in

Britain Britain most often refers to: * Great Britain, a large island comprising the countries of England, Scotland and Wales * The United Kingdom of Great Britain and Northern Ireland, a sovereign state in Europe comprising Great Britain and the north-eas ...

File:16-11-18-Holzfelge mit Schlauchreifen-RR2 7364.jpg, Wooden bicycle rim with tubular tyre and a Presta valve File:Bicycle wheel with wooden rim detail 2.jpg, Detail of wooden rim for tubular tires

References

{{Tires Tires