Tubular tyres
Encyclopedia
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
Bicycle tire
A bicycle tire is a tire that fits on the wheel of a bicycle, unicycle, tricycle, quadracycle, bicycle trailer, or trailer bike. They may also be used on wheelchairs and handcycles, especially for racing...

 that is stitched closed around the inner tube to form a torus. 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
Bicycle wheel
A bicycle wheel is a wheel, most commonly a wire wheel, designed for bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels....

.

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, but tubulars are still commonly used for indoor track racing (where the closed track makes punctures from road debris
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...

 less commonplace), professional road racing
Road bicycle racing
Road bicycle racing is a bicycle racing sport held on roads, using racing bicycles. The term "road racing" is usually applied to events where competing riders start simultaneously with the winner being the first to the line at the end of the course .Historically, the most...

, and road time trials.

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 usually 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.

Other advantages of this system include a decreased chance of pinch flats, it can be made to operate in a wider range of tyre pressures (from 25 to 200 psi). Furthermore, when a tubular goes flat at high speed there is a safety margin because it will not roll off the rim if it is properly glued on.

Tubular tyres are fitted with Presta valve
Presta valve
The Presta valve is a valve commonly found in high pressure road style and many mountain bicycle inner tubes. It comprises an outer valve stem and an inner valve body...

s.

A tubeless tubular, with an integrated airtight liner instead of a separate inner tube, has been introduced.
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