![16-11-18-Holzfelge mit Schlauchreifen-RR2 7364](https://upload.wikimedia.org/wikipedia/commons/7/7c/16-11-18-Holzfelge_mit_Schlauchreifen-RR2_7364.jpg)
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
A bicycle tire is a tire that fits on the Bicycle wheel, wheel of a bicycle or similar vehicle. These tires may also be used on tricycles, wheelchairs, and handcycles, frequently for Wheelchair racing, racing. Bicycle tires provide an importa ...
that is stitched closed around the
inner tube
An inner tube is an inflatable ring that forms the interior of some pneumatic tires. The tube is inflated with a valve stem, and fits inside of the casing of the tire. The inflated inner tube provides structural support and suspension, while the ...
to form a
torus
In geometry, a torus (plural tori, colloquially donut or doughnut) is a surface of revolution generated by revolving a circle in three-dimensional space about an axis that is coplanar with the circle.
If the axis of revolution does not tou ...
. 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 ...
.
Tubular tyres require more labour to repair a puncture than
clincher tyres (wired–on in Britain). The tyre must be removed from the rim, opened up, patched, sewn back up, then finally glued back to the rim. Clinchers have largely replaced tubulars for amateur racing (although they have seen a revival due to the carbon rim being better suited to tubular design), but tubulars are still commonly used for indoor track racing (where the closed track makes punctures from
road debris
Road debris, a form of road hazard, is debris 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 sources, but in all ...
less commonplace), professional
road racing
Road racing is a form of motorsport racing held on a paved road surface. The races can be held either on a closed circuit or on a street circuit utilizing temporarily closed public roads. Originally, road races were held almost entirely on publ ...
, road time trials, and
cyclo-cross racing.
The resulting combination was either slightly lighter or stronger than more common clincher tyres until the clincher tyres and rims technology caught up in recent years. Taken as a whole the total weight of a tubular rim and tyre is always lighter than its clincher equivalent. However, for all non-racing purposes the 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 if using clincher tyres). Yet the extra weight—and more importantly, rotational inertia—is off the wheel, which therefore accelerates more easily. Advances in tire sealant have made carrying an extra tire a bit outdated.
Other advantages of this system include a decreased chance of pinch flats,
an ability to operate with a wider range of tyre pressures (from 25 to 200 psi), and increased safety in the event of a flat at high speed because a properly glued on tubular tyre is less likely to roll off the rim.
A further advantage is that because a tubular tyre is an inner tube within the outer tyre casing, it is a "closed system," meaning in the event of a flat 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. Conversely, they are also regarded as being ''less'' safe on long or fast descents, because the heat generated by braking can cause the glue holding the tire to the rim to fail, or the tire to explode.
Tubular tyres are fitted with
Presta valve
The Presta valve (also French valve (FV) or Sclaverand valve) is a tire valve commonly found in high pressure road style and some mountain bicycle inner tubes. It comprises an outer valve stem and an inner valve body. A lock nut to secure the s ...
s.
A tubeless tubular, with an integrated airtight liner instead of a separate inner tube, was introduced in 2009.
Gallery
File:Bicycle rim diagrams 04.png, Rims for tubular tyres, referred to as "sprint rims" in Britain
Britain most often refers to:
* The United Kingdom, a sovereign state in Europe comprising the island of Great Britain, the north-eastern part of the island of Ireland and many smaller islands
* Great Britain, the largest island in the United King ...
File:Bicycle wheel with wooden rim detail 2.jpg, Detail of wooden rim for tubular tyres
File:1933 SpeicherLeducq.jpg, André Leducq
André Leducq (; 27 February 1904 – 18 June 1980) was a French cyclist who won the 1930 and 1932 Tours de France. He also won a gold medal at the 1924 Summer Olympics in the team road race event and the 1928 Paris–Roubaix.
Career
Ledu ...
and Georges Speicher
Georges Speicher (; 8 June 1907 – 24 January 1978) was a French cyclist who won the 1933 Tour de France along with three stage wins, and the 1933 World Cycling Championship.
After Speicher had won the 1933 Tour de France, he was initially not ...
in the 1933 Tour de France
The Tour de France () is an annual men's multiple-stage bicycle race primarily held in France, while also occasionally passing through nearby countries. Like the other Grand Tours (the Giro d'Italia and the Vuelta a España), it consists ...
carrying spare tubular tyres on their shoulders
References
{{Tires
Tires