Tubular tyre
{{For|tires used with inner tubes|Tire#Inner tube}}
File:Tubular Tyre Cut Open 06.jpg powder to prevent it from sticking to itself.]]
A tubular tyre, referred to as a tub in Britain,{{cite web | url= https://www.sheldonbrown.com/gloss_tp-z.html | title= Sheldon Brown's Glossary Tp-Z: Tub | author= Sheldon Brown | accessdate= 2016-09-28 | authorlink= Sheldon Brown (bicycle mechanic)}} a sew-up in the US, a single in Australia{{fact|date=August 2023}}, or just a tubular is a bicycle tyre 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,{{cite book |last= St. Pierre |first= Roger |title= The Book of the Bicycle |publisher= Tribune Books Press |year= 1978 |pages= 24–26 |ref= St. Pierre1978 |isbn= 0-85674-016-0}}{{cite web | url= https://www.sheldonbrown.com/gloss_sp-ss.html | title= Sheldon Brown's Bicycle Glossary Sp-Ss: Sprint | author= Sheldon Brown | quote= British: a rim designed for tubular tyres. | accessdate= 2010-03-22 | authorlink= Sheldon Brown (bicycle mechanic)}} and just a "tubular rim" in the US,{{cite web | url= https://www.parktool.com/blog/repair-help/tubular-tire-gluing-sew-up | title= Tubular Tire Gluing | publisher= Park Tools | quote= The tubular is then glued to a special rim, called a tubular rim. | accessdate= 2010-03-24}} of a bicycle wheel.
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.{{cite book|url=https://books.google.com/books?id=f_ZFHAAACAAJ|title=Guide to Tubular Tyres, Including Sprint Rims|author=Arthur S. Waltho|year=1964}} Tubulars can also be used over a wider range of tyre pressures from 1.7 to 14 bar (25 to 200 psi), compared to the typical 6-9 bar on a clincher tyre.
History
File:1933 SpeicherLeducq.jpg and Georges Speicher in the 1933 Tour de France carrying spare tubular tyres on their shoulders]]
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.{{citation needed|date=June 2023}}
In the 2010s, tubular tyres were still commonly used for indoor track racing (where the closed track makes punctures from road debris less commonplace), professional road racing, road time trials, and cyclo-cross racing.{{citation needed|date=June 2023}}
In 2009, a tubeless tubular with an integrated airtight liner instead of a separate inner tube was introduced.{{cite web | url= https://www.bike-eu.com/home/nieuws/2009/01/tufo-tubeless-road-racing-tyres-1013856 | title= Bike Europe: Tufo Tubeless Road Racing Tyres | date= 2009-01-15 | accessdate= 2016-12-10}}
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.{{Citation needed|reason=This justification is vague and needs a source.|date=October 2017}} For this reason tubulars are generally regarded{{By whom|date=October 2017}} 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.{{cite web|access-date=2023-06-18|date=2017-10-28|title=Tubulars vs. Clinchers|url=https://abovecategory.com/blogs/journal/tubulars-vs-clinchers|work=Above Category}}
= Heating from rim brakes =
Tubular tyres can be less safe with rim brakes on long descents because the heat generated by braking can cause the glue holding the tyre to the rim to fail.{{cite web |url= http://www.cyclingnews.com/news/tour-de-france-keldermans-crash-due-to-melting-tubular-glue/ |title= Tour de France: Kelderman's crash due to melting tubular glue |accessdate= 2017-10-30}}
Additionally, excessive heat from rim brakes can cause the tyre pressure to increase so much that the tyre can explode,{{cite web |url= https://www.velonews.com/2015/02/bikes-and-tech/technical-faq-hot-tires-rims-oman_361634 |accessdate= 2017-10-30 |title= Technical FAQ: Hot tires and rims in Oman}} 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 valves.
Gallery
File:Bicycle rim diagrams 04.png|Rims for tubular tyres, referred to as "sprint rims" in Britain
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