29ers or two-niners are mountain bikes and hybrid bicycles built to use ISO 700c or 622Ã, Â ° (in rim diameter) wheels, commonly called 29 "wheels. Most mountain bikes once use a 559 mm ISO wheel, commonly called a 26 "wheel. ISO 622 mm wheels are usually also used for street racing, trekking, cyclo-cross, touring, and hybrid bikes. In some countries, especially in Continental Europe, ISO 622 mm wheels are generally called 28 "or" 28 Incher "wheels.
Video 29er (bicycle)
Origins
The 29er rim has a diameter of 622 millimeters (24.5 inches) and an average 29 "mountain bike tire is (in ISO notation) 59-622 - corresponding to an outside diameter of about 29.15 inches (740 mm) General 26" MTB tires has a rim diameter of 559 millimeters (22.0 inches) and an outer tire diameter of about 26 inches (660 mm).
In the early 1980s, the size of the wheels for the emerging mountain bikes had not yet been decided. So when British offshore cyclists Geoff Apps contacted Gary Fisher and Charlie Kelly with the news that he had built an off-road bike prototype that uses a large diameter of 28 x 1Ã,¾ (ISO 47-622), the 47mm Nokian Hakkapeliitta snow of Finland , they are interested. In a letter to the December 2006 issue of Bike Biz, Gary Fisher, talking about the growing popularity of 29ers, gave his perspective: "We got some tires from Geoff Apps really early and we [Fisher and Kelly] say 'Holy Toledo' But the supply situation the worse of larger diameter tires means the new MTB industry is stuck with smaller wheel sizes. "The first Geoff Apps designed 700C off-road bike was built in 1981.
However, bikes that were marketed as an Aventura company by Apps themselves, Cleland Cycles Ltd, between 1982 and 1984 used Nokian Hakkapeliitta 26 ÃÆ'â € "2 (ISO 54-584) which was more readily available. The 650B size, also known as 27.5 ", reappeared in 2007 as a compromise between the size of 26 inches and 29 inches.The size of 650B is called 27.5".
The name "29er" comes from a bicycle called Two Niner, offered by the bicycle company Fisher in 2001, according to a 1998 Mountain Bike Hall of Fame induced Don Cook.
The US Division of Bianchi Bicycles offers a line of 29 "wheeled off-wheel bicycles beginning in 1991 called Project bikes, their 1992 product catalog babbling about the advantages of larger wheels and showing three different bikes, Project 3, 5 and 7 original Klein Company produced a small number of "wheel" versions of "29" from the successful MTB "Attitude" racer, and named it Adept. Failed to find the market and stopped. In the mid-1990s, Diamondback Bicycles made their Overdrive motors, and Specialized made their Crossroads bicycles with 700C wheels, but they were actually hybrid bikes with framework and fork cleans for larger tires. The Project and Overdrive bikes were unsuccessful due to various reasons, mainly due to the lack of proper off-road tires and suspension forks that competed with the 26 "offer at the time.
The main product release, the first true 29 "tire, was produced by an early supporter of the 29" Wilderness Trail Bikes movement. The company introduced the first true 29 "tire, Nanoraptor, in 1999. At about the same time, the White Brothers produced the first commercially available 29" suspension fork. Before that the suspension fork used was a fork designed for bicycle or hybrid trekking. Over the years, 29 "frames and bikes are usually only available from smaller, lesser known factories such as Niner Bikes.Bike Surly introduced 29" frameset, Karate Monkey, in 2002. Gary Fisher Bicycles, the division of Bicycle Tracks, became the first of the manufacturing large to offer a line of 29 "bikes.Their line never sold well until the introduction of a single speed 29" Rig bike, in 2004. Today, most bicycle manufacturers in the US market offer at least one 29 "bike or frame. openly reject 29 "as a bad idea or a passing trend, Specialized and Turner, brings 29" wheels to the market.
Maps 29er (bicycle)
Cyclocross Comparison
A tire with a tread width of less than 2.0 inches (51 mm) wide is sometimes considered a cyclocross tire by 29 "fans, although the cyclocross tires are wider than 1.5 in (38 mm) instead of cyclocross tires. is intended for off-road use, and typically uses 62 mm tires, cyclocross bicycles and 29 "wheeled MTBs differing in basic handling and geometry, construction methods, durability, and intended lifespan. Bicycles exist that blur the difference by combining both attributes, however. One example is the Monstercross bicycle, often using standard mountain bike frames intended for use with 26 "wheels with 700c wheels and 700 x 38c-45c tires, disc brakes or cantilever, MTB or cross gears, and cyclocross bike drop bars.
Performance
The advantages and disadvantages of 29ers are often disputed in the mountain bike community. The shortcomings of the 29 "wheel include weight gain, delays in handling, and problems with fit (in particular, front wheel/toe overlap and high high height.) Benefits include reduced rolling resistance, increased stability while maintaining rapid handling, ability to roll over obstacles.
One of the items that is often lifted is the size and shape of the tire contact patch. All the same, such as tire width, rim width, inflation pressure and rider weight, contact patches of 29 "wheels have the same area and are slightly longer (~ 5%) compared to 26" wheels.
Benefits
- Bigger wheels overthrow obstacles easier. The ability of the wheel to overthrow obstacles is proportional to its size. The 29 "wheels, which are about 10% larger than the 26" wheels, can roll over 10% larger obstacles.
- Larger diameter wheels have greater angular momentum so they lose less speed to obstacles and rough parts but the same effect can be achieved with larger tires.
- 29 "bikes tend to offer the rider a higher" natural "frame geometry
Most of these claims have not been investigated objectively. Small scale, unpublished studies (including those conducted by Pepperdine University, reported at the request of Gary Fisher) exist, but both supporters and critics of the wheel 29 "are generally not impressed with their scientific rigor.Such debate about how to conduct a fair" efficiency "of mountain bikes 29 "vs. 26" has been raging online, but no serious effort has been made to undertake large-scale scientific research.
Weakness
- The increased wheel weight (tires, tubes, rims, and bigger radius) makes the wheel slower to respond to acceleration and braking, and adds unsprung mass.
- Longer radius and decreasing angle between the hub and rim flanges result in a more flexible wheel lateral ( ceteris paribus ).
- Less responsive handling due to a longer wheelbase and a heavier front wheel.
- Smaller riders (ie, less than 5'5 "(= 165Ã, cm) tall) may face significant geometric sacrifices, possibly resulting in leg overlap, high handlebar height, and fewer clearance clearances. li>
96 or 69 variations
One variation is having a 29 "front wheel and 26" rear wheels (commonly called "96er"). Using the smaller rear wheels allows for shorter and faster handling frames, more options for rear suspension design and lighter weight bikes. Another variation is having a 26 "front wheel with 29" rear wheels (commonly called "69er" though Tracks introduced "69er" in 2007 with 29 "front wheels and 26" rear wheels).
See also
- 27.5 Mountain bikes
- Mountain bikes
- Bike descending
- Glossary of cycling
- Outline biking
References
External links
- an article about bicycle tires and rim size from Sheldon Brown's website
- Cycling News Articles compares 26 "and 29" performance
- Big Wheel or Small Wheel ?, Juli Lennard Zinn, VeloNews 2005 article
Source of the article : Wikipedia
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