A motorcycle fairing is a shell placed over the frame of some motorcycles racing motorcycles and sport bikes, with the primary purpose to reduce air drag. The secondary functions are the protection of the rider from airborne hazards and wind-induced hypothermia and of the engine components in the case of an accident. A motorcycle windshield will always be integrated into the design of the fairing; the major benefit of a fairing on sport touring and touring motorcycles is a reduction in aerodynamic drag, which allows for reduced fuel consumption and permits higher speeds at lower engine rpm, which in turn increases engine life. A motorcycle may have a rear fairing, a belly fairing, or any combination of these. Alternatively, a single fairing may or enclose the entire motorcycle, may enclose the rider; the importance of streamlining was known early in the 20th century, some streamlining was seen on racing motorcycles as early as the 1920s. Although motorcycles have a much higher power-to-weight ratio than cars, bikes – and the rider – are much less streamlined and the effects of aerodynamic drag on motorcycles are significant.
Any reduction in a motorcycle's drag coefficient pays dividends in improved performance. The term fairing came into use in aircraft aerodynamics with regard to smoothing airflow over a juncture of components where airflow was disrupted. Early streamlining was unsuccessful resulting in instability. Handlebar fairings, such as those on Harley-Davidson Tourers, sometimes upset the balance of a motorcycle, inducing wobble; the fairings were cowlings put around the front of the bike, increasing its frontal area. They became an integral part of the design. Modern fairings increase the frontal area at most by 5% compared to a naked machine. Fairings may carry headlights and other items. If the fairing is mounted on the frame, placing other equipment on the fairing reduces the weight and rotational inertia of the steering assembly, improving the handling; the BMW R100RS, produced from 1976 to 1984, was the first mass-market sport touring motorcycle to be offered with a full fairing as standard, marked the beginning of wider adoption of fairings on sports and touring types of motorcycles.
The integrated design included a development of the frame-mounted tail fairing at the rear of the removable dual seat accessing a storage compartment used on the BMW R90S from 1973 being the first example of a factory-fitted head fairing. A single piece, streamlined shell covering the front half of a motorcycle resembling the nose of an aircraft, sometimes referred to as torpedo fairing, it reduced the frontal drag, but it was banned by Fédération Internationale de Motocyclisme from racing in 1958, because it was thought that the frontal point of wind pressure made them unstable with small amounts of yaw. Other reasons cited for the ban were to ensure adequate steering stability in crosswinds. FIM regulations forbid streamlining beyond the wheel spindles and require the rider's arms and legs to be visible from the side. However, Peter Williams was permitted to give his 1973/74 JPS Norton a Peel-type fairing incorporating handlebar blisters which helped to reduce the drag coefficient to 0.39.
This was called so because, in early models, the front wheel mudguard streamlined with the rising windshield part of the fairing resembled the dolphin's snout from the side view. Further developments on this design became the norm. A full fairing is a large front-mounted fairing, should not be confused with cabin motorcycle or streamliner motorcycle fairings which or enclose the entire motorcycle. Full fairings cover both upper and lower portions of the motorcycle, as distinct from a half fairing, which only has an upper section, leaves the lower half of the motorcycle exposed; the fairing on a race or sport bike is meant as an aerodynamic aid, so the windscreen is looked through. If the rider is sitting up at speed he will be buffeted by his rapid progress through the air and act as a parachute, slowing the bike, while if the rider lies flat on the tank behind the windscreen he generates much less aerodynamic drag; the high windscreen and handlebar width of a touring fairing protect the upright rider from the worst of this, the windscreen is functional.
Full fairings can provide protection to the engine and chassis in the event of a crash where the fairings, rather than the engine covers and/or frame, slide on the road. Half fairings feature a windscreen and extend below the handlebars as far down as the sides of the cylinder block, but do not cover the sides of the crankcase or gearbox. Aftermarket kits –'lowers' – are available to extend some half fairings into full fairings. Due to the popularity of these kits, some motorcycle manufacturers have started to supply their own full fairing conversion kits and offer their half faired models new with a full factory-fitted kit. A windscreen and minimal fairing extending around the headlamp fixed to the triple clamp. Called a café fairing or bikini fairing, it stops well below the level of the rider's head, relying on air deflection to protect the rider's head and chest from the slipstream. Whereas the other types of fairing are all fixed to the main chassis of the bike and don't move, the handlebar fairing complete with screen is like an expanded/extended nacelle and is attached only to the forks/yokes, encompassing the headlight/s and clocks and varying amounts of the handlebars, it moves with them as the bars are turned and indicators move like on a naked bike instead of being fixed straight ahe
International Standard Serial Number
An International Standard Serial Number is an eight-digit serial number used to uniquely identify a serial publication, such as a magazine. The ISSN is helpful in distinguishing between serials with the same title. ISSN are used in ordering, interlibrary loans, other practices in connection with serial literature; the ISSN system was first drafted as an International Organization for Standardization international standard in 1971 and published as ISO 3297 in 1975. ISO subcommittee TC 46/SC 9 is responsible for maintaining the standard; when a serial with the same content is published in more than one media type, a different ISSN is assigned to each media type. For example, many serials are published both in electronic media; the ISSN system refers to these types as electronic ISSN, respectively. Conversely, as defined in ISO 3297:2007, every serial in the ISSN system is assigned a linking ISSN the same as the ISSN assigned to the serial in its first published medium, which links together all ISSNs assigned to the serial in every medium.
The format of the ISSN is an eight digit code, divided by a hyphen into two four-digit numbers. As an integer number, it can be represented by the first seven digits; the last code digit, which may be 0-9 or an X, is a check digit. Formally, the general form of the ISSN code can be expressed as follows: NNNN-NNNC where N is in the set, a digit character, C is in; the ISSN of the journal Hearing Research, for example, is 0378-5955, where the final 5 is the check digit, C=5. To calculate the check digit, the following algorithm may be used: Calculate the sum of the first seven digits of the ISSN multiplied by its position in the number, counting from the right—that is, 8, 7, 6, 5, 4, 3, 2, respectively: 0 ⋅ 8 + 3 ⋅ 7 + 7 ⋅ 6 + 8 ⋅ 5 + 5 ⋅ 4 + 9 ⋅ 3 + 5 ⋅ 2 = 0 + 21 + 42 + 40 + 20 + 27 + 10 = 160 The modulus 11 of this sum is calculated. For calculations, an upper case X in the check digit position indicates a check digit of 10. To confirm the check digit, calculate the sum of all eight digits of the ISSN multiplied by its position in the number, counting from the right.
The modulus 11 of the sum must be 0. There is an online ISSN checker. ISSN codes are assigned by a network of ISSN National Centres located at national libraries and coordinated by the ISSN International Centre based in Paris; the International Centre is an intergovernmental organization created in 1974 through an agreement between UNESCO and the French government. The International Centre maintains a database of all ISSNs assigned worldwide, the ISDS Register otherwise known as the ISSN Register. At the end of 2016, the ISSN Register contained records for 1,943,572 items. ISSN and ISBN codes are similar in concept. An ISBN might be assigned for particular issues of a serial, in addition to the ISSN code for the serial as a whole. An ISSN, unlike the ISBN code, is an anonymous identifier associated with a serial title, containing no information as to the publisher or its location. For this reason a new ISSN is assigned to a serial each time it undergoes a major title change. Since the ISSN applies to an entire serial a new identifier, the Serial Item and Contribution Identifier, was built on top of it to allow references to specific volumes, articles, or other identifiable components.
Separate ISSNs are needed for serials in different media. Thus, the print and electronic media versions of a serial need separate ISSNs. A CD-ROM version and a web version of a serial require different ISSNs since two different media are involved. However, the same ISSN can be used for different file formats of the same online serial; this "media-oriented identification" of serials made sense in the 1970s. In the 1990s and onward, with personal computers, better screens, the Web, it makes sense to consider only content, independent of media; this "content-oriented identification" of serials was a repressed demand during a decade, but no ISSN update or initiative occurred. A natural extension for ISSN, the unique-identification of the articles in the serials, was the main demand application. An alternative serials' contents model arrived with the indecs Content Model and its application, the digital object identifier, as ISSN-independent initiative, consolidated in the 2000s. Only in 2007, ISSN-L was defined in the
Bicycle and motorcycle geometry
Bicycle and motorcycle geometry is the collection of key measurements that define a particular bike configuration. Primary among these are wheelbase, steering axis angle, fork offset, trail; these parameters have a major influence on. Wheelbase is the horizontal distance between the centers of rear wheels. Wheelbase is a function of rear frame length, steering axis angle, fork offset, it is similar to the term wheelbase used for trains. Wheelbase has a major influence on the longitudinal stability of a bike, along with the height of the center of mass of the combined bike and rider. Short bikes are much more suitable for performing stoppies; the steering axis angle called caster angle or head angle, is the angle that the steering axis makes with the horizontal or vertical, depending on convention. The steering axis is the axis; the steering axis angle matches the angle of the head tube. In bicycles, the steering axis angle is measured from the horizontal. For example, Lemond offers: a 2007 Filmore, designed for the track, with a head angle that varies from 72.5° to 74° depending on frame size a 2006 Tete de Course, designed for road racing, with a head angle that varies from 71.25° to 74°, depending on frame size.
Due to front fork suspension, modern mountain bikes - as opposed to road bikes - tend to have slacker head tube angles around 70° although they can be as low as 62°. At least one manufacturer, Cane Creek, offers an after-market threadless headset that enables changing the head angle. In motorcycles, the steering axis angle is called the rake angle or just rake and is measured from the vertical. For example, Moto Guzzi offers: a 2007 Breva V 1100 with a rake of 25°30’ a 2007 Nevada Classic 750 with a rake of 27.5° The fork offset is the perpendicular distance from the steering axis to the center of the front wheel. In bicycles, fork offset is called fork rake. Road racing bicycle forks have an offset of 40–50 mm; the offset may be implemented by curving the forks, adding a perpendicular tab at their lower ends, offseting the fork blade sockets of the fork crown ahead of the steerer, or by mounting the forks into the crown at an angle to the steer tube. The development of forks with curves is attributed to George Singer.
In motorcycles with telescopic fork tubes, fork offset can be implemented by either an offset in the triple tree, adding a triple tree rake to the fork tubes as they mount into the triple tree, or a combination of the two. Other, less-common motorcycle forks, such as trailing link or leading link forks, can implement offset by the length of link arms; the length of a fork is measured parallel to the steer tube from the lower fork crown bearing to the axle center. Trail, or caster, is the horizontal distance from where the front wheel touches the ground to where the steering axis intersects the ground; the measurement is considered positive if the front wheel ground contact point is behind the steering axis intersection with the ground. Most bikes have positive trail, though a few, such as the two-mass-skate bicycle and the Python Lowracer have negative trail. Trail is cited as an important determinant of bicycle handling characteristics, is sometimes listed in bicycle manufacturers' geometry data, although Wilson and Papodopoulos argue that mechanical trail may be a more important and informative variable, although they both describe nearly the same thing.
Trail is a function of steering axis angle, fork offset, wheel size. Their relationship can be described by this formula: Trail bicycle = R w cos − O f sin and Trail motorcycle = R w sin − O f cos where R w is wheel radius, A h is the bicycle head angle measured from the horizontal, A r is the motorcycle rake angle measured from the vertical, O f is the fork offset. Trail can be increased by increasing the wheel size, decreasing or slackening the head angle, or decreasing the fork offset. Trail decreases as head angle increases, as wheel diameter decreases. Motorcyclists tend to speak of trail in relation to rake angle; the larger the rake angle the larger the trail. Note that, on a bicycle, as rake angle increases, head angle decreases. Trail can vary as the bike steers. In the case of traditional geometry, trail decreases as the bike leans and steers in the direction of
Harley-Davidson Tri Glide Ultra Classic
The Harley-Davidson Tri Glide Ultra Classic is a three-wheeled motorcycle manufactured by Harley-Davidson and introduced in the 2009 model year. Its model designation is FLHTCUTG; the Tri Glide Ultra Classic is the first three-wheeled motorcycle produced by Harley-Davidson since the Harley-Davidson Servi-Car, manufactured from 1932 to 1973. The Tri Glide is based on the Harley-Davidson Electra Glide Ultra Classic, a conventional two-wheeled touring motorcycle. Harley-Davidson entered into an agreement in 2008 with Lehman Trikes of Spearfish, South Dakota to provide parts and "conversion services", final assembly of the Tri Glides was completed at Lehman's facility. Company owner John Lehman died in January, 2012, the Tri Glides are now assembled at the Harley-Davidson plant in York, Pennsylvania. Shortly after the product introduction, a Tri Glide led the way in the parade at the Inauguration of Barack Obama on January 20, 2009. Harley-Davidson offered a second trike model called the Street Glide Trike with fewer standard features, starting in the 2010 model year.
The Street Glide Trike is no longer manufactured. Harley released a new trike model in the Harley-Davidson Freewheeler; because of its inherent stability, the Tri Glide, like other three-wheeled motorcycles, is marketed to motorcycle riders who are experiencing health problems due to aging or injuries, to female riders. Three-wheeled motorcycles comprise a "significant niche" in the current motorcycle market; the Tri Glide is powered by a 103 cu in overhead valve V-twin engine that produces a claimed 101 ft lbs of torque and 70 rear wheel horsepower, is equipped with a six speed transmission. The engine has electronic fuel injection. Electric powered reverse was available as an option when the Tri Glide was introduced, but became a standard feature. Electronic cruise control is standard. List of motorized trikes Harley-Davidson Media Site: FLHTCUTG Tri Glide Ultra Classic
Harley-Davidson Twin Cam engine
The Harley-Davidson Twin Cam engines are motorcycle engines made by Harley-Davidson since 1998. Although these engines differed from the Evolution engine, which in turn was derived from the series of single camshaft, overhead valve motors that were first released in 1936, they share a number of characteristics with nearly all previous Harley-Davidson engines. Both engines have two cylinders in a V-twin configuration at 45°, are air-cooled, activate valves with push-rods; the crankshafts have a single pin with a fork arrangement for the connecting rods. These are sandwiched between a pair of flywheels; the Twin Cam 88 was released for the 1999 model year in September 1998. The Twin Cam 96 was released for the 2007 model year; the Twin Cam was not used in the Softail model family before the year 2000. This was due to the chassis design and vibration transfer to the Softail frame as a result of the direct mounting of the engine. Dyna models are "rubber mounted", damping the majority of vibration transfer to the rider.
Another reason was that the engine and transmission on a Twin Cam are directly bolted to each other, with the chassis seat post on a Softail getting in the way of a Twin Cam transmission case. As the company determined that a rubber-mounted Softail would affect the line's visual styling, Harley solved the issue by designing an engine variant known as Twin Cam 88B, it is the same engine as the original, but with a modified engine block design that incorporates twin chain-driven balance shafts. The Twin Cam 96B engine was released at the same time as the Twin Cam 96A model, for the 2007 model year, was equipped on all Softail models until it was replaced by the 103 ci version, it is possible, however, to mount a regular Twin Cam motor to a pre-2000 Softail through third-party adapters. The engine design differed from its predecessor the "Evo" although it shared some design elements with the Sportster line; the 88 represents the displacement in cubic inches of the standard engine. The bore is 3.75 in and the stroke is 4.00 in, meaning the displacement is 88 cu in.
The Twin Cam 96 displaces 96.7 cu in. The company released 103 cu in for 2010 Electra Glide Ultra Limited models, for 2012 Softail models and 110 cu in for Screamin' Eagle/CVO Models. Development of the Twin Cam started in the early 1990s, as Harley sought to address problems affecting the previous Evolution engine structural weaknesses within the crankcase, oil circulation and leakages. While aftermarket firms such as S&S Cycle responded with stronger crankcase components for high-performance Evolutions, Harley went for a new design, while keeping the engine fundamentally and aesthetically similar to the traditional 45-degree, air-cooled overhead valve V-twin; the Twin Cam only shared 18 parts with its predecessor, as all of the components were unique to the engine. As the name implies, the engine uses two chain-driven cams; the drivetrain was reinforced through a mounting scheme called the "Revised Rear Interface", allowing the transmission case to be mounted directly to the rear of the engine, with the primary drive and clutch covers playing less of a structural role.
The early prototype Twin Cam engines had considerable trouble with the oiling system. These problems delayed release of the engine; when the engines were run, oil came out any gasketed joint as well as the breather. Harley sought the help of Paul Troxler, a young engineer from Southwest Research Institute and the problem was traced to a design which drained the cam case into the crankcase, used a single scavenge pump. Due to airflow through ports in the crankcase wall, the cam case was not draining properly. After much testing, the solution was to seal the cam case from the crankcase and use a dual scavenge system, incorporated into the engine, rather than as an outboard pump as used on older Big Twins since the original Knucklehead. However, oil was still not scavenging properly from the crankcase, this was traced to an acoustic phenomenon due to the caliber of the scavenge inlet. Restricting the diameter of the inlet, a counter-intuitive solution, solved that problem. Detailed Harley Twin Cam Engine Animations
The Harley-Davidson Sportster is a line of motorcycles produced continuously since 1957 by Harley-Davidson. Sportster models are designated in Harley-Davidson's product code by beginning with "XL". In 1952, the predecessors to the Sportster, the Model K Sport and Sport Solo motorcycles, were introduced; these models K, KK, KH, KHK of 1952 to 1956 had a sidevalve engine, whereas the XL Sportster models use an overhead valve engine. The first Sportster in 1957 had many of the same details of the KH including the frame, large gas tank and front suspension. Sportster motorcycles are powered by a four-stroke, 45° V-twin engine in which both connecting rods, of the "fork and blade" or "knife & fork" design, share a common crank pin; the original Sportster engine was the Ironhead engine, replaced with the Evolution engine in 1986. Sportster engines, the 45 cubic inch R, D, G & W Models 1929 side-valve motors, the'Big Twin' side-valve motors, which were: the flathead 74.0 cu in Models V, VL etc. Models U and UL, the 80.0 cu in models VH and VLH, models UH and ULH have four separate cams, sporting one lobe per cam.
The cam followers used in Sportster engines, K models, big twin side valve models, the side-valve W model series were a shorter version of the followers used in the larger motors, but with the same 0.731-inch diameter body and 0.855-inch diameter roller follower since 1929. The company used similar cam followers for decades with minor changes, from the 1929 to the Eighties. Sportster engines retained the K/KH design crankcase design, in which the transmission is contained in the same casting as the engine, driven by the engine with a triple-row #35 chain primary drive and a multi-plate cable-operated clutch. Models since 1991 have five speeds; the engine was mounted directly to the frame from 1957 through the 2003 model year. While this system allows the bike to be somewhat lighter with more precise handling, it transmits engine vibration directly to the rider. In 2003 Harley Davidson produced, they are identified by the 100 year anniversary paint schemes and plaques attached to the tinware, speedo housing and on the engine.
Sportsters released in 2004 and use rubber isolation mounts and tie links to limit engine movement to a single plane, which reduces vibration felt by the rider. Buell motorcycles built with variants of the Sportster engine have used a rubber mount system since 1987; the Model K, from which the Sportster evolved, was the first civilian motorcycle produced by Harley-Davidson with hydraulic shock absorbers on both wheels. Common usage calls this a K Model; this is developed from the earlier 45 W model, but with the revised flat head engine and new 4-speed transmission contained in the same castings as would become the Sportster. The connecting rods would be inherited by the Sportster along with many other design elements and dimensions. Model K and KK 1952–1953: 750 cc side-valve engines, using the 45 model bore and stroke of 2.75" x 3.8125" Model KR 1953–1969: 750 cc side-valve engines Model KH and KHK 1954–1956: 888 cc side-valve engines, using the 45 model bore, but with the stroke increased to 4.5625".
This is the only small twin with a longer stroke than 3.8125". The shorter stroke is otherwise universal to the entire 45/K/Sportster line from 1929 to the present. XL, Ironhead, 1957–1985: 883 cc and 1,000 cc Ironhead overhead-valve engines with cast iron heads, K series frame XLCH, Ironhead, 1958–1971: 883 cc, 1,000 cc 1972 & up XR-750 1970–1971: 750 cc overhead-valve engine, iron heads XR-750 1972–1985: 750 cc overhead-valve engine, alloy heads XLCR 1977–1978-1979: Cafe racer 1,000 cc overhead-valve engine, iron heads, 2000 made in 77, 1200 in 78, 9 in 1979 XR-1000 1983–1984: 1,000 cc street model using XR racing cylinder head and other XR engine parts XLR: 883 cc overhead-valve engines, iron heads XLS Roadster 1979-1982 1000cc ironhead / 4 speed, stock components—2" longer forks, 2 up seat, sissy bar, highway pegs, 2.2 gallon tank XLS Roadster, 1983-1985, 1,000 cc ironhead, 4 gallon fuel tank with console XL, since 1986: 883 cc, 1,100 cc and 1,200 cc Evolution overhead-valve engine, alloy heads 1957 "Ironhead" overhead-valve engine introduced.
1958 XLH touring high compression model and XLCH sportier "Competition Hot" model introduced. 1967 Electric starting introduced on XLH 1972 "Ironhead" 1,000 cc overhead-valve engine replaces 900 cc. Claimed power was 61 hp @ 6,200 rpm and a top speed of 116 mph 1975 Switched to left-side gear change 1977 & 1979 Dual exhaust "Siamese" pipes used, introduced on Willie G. Davidson's XLCR café racer in 1977 all models 1979, along with the triangular frame and rear hydraulic disk brake introduced on the XLCR. In 1977 a limited edition Confederate Edition Sportster was introduced for one year only. 1979 Last year for the kickstart only XLCH, only 141 made. 1985 Last year for the "Ironhead" overhead-valve engine. 1986 "Evolution" engine introduced in 1,100 cc sizes. 1988 1200 cc engine replaces 1,100 cc engine. 1988 Constant velocity carburetor replaces butterfly carburetor. 1991 Five-speed transmission replaces four-speed. 1991 Belt drive replaces chain drive on all 1200 models. 1993 Belt drive made standard on all Sportsters.
1994 Improved oil tank, bat
A softail is a motorcycle with its rear suspension springs or shock absorbers located out of direct view, so as to look like a hard-tail motorcycle. The word softail is a registered trademark of Harley-Davidson, coined for the FXST Softail in 1984. Softail has become a genericized trademark, referring to other brands of motorcycles with hidden rear suspensions, extended to bicycles as well; the Harley-Davidson softail frame is designed to look like the rigid frame bikes of the past, while still having the comfort of rear suspension. The shock absorbers are positioned along the axis of the motorcycle, tucked under the transmission on models from 1984 to 2017 and under the seat on 2018 models. There have been many Harley-Davidson models with the Softail frame, including the Softail Standard, Springer Softail, Heritage Softail, Heritage Springer, Night Train, Deuce, Fat Boy, Softail Slim, the Dark Custom Cross Bones, the Dark Custom Blackline and Breakout. With the exception of the Deuce, which has a 2 in longer backbone, these motorcycles have the same engines and frames, differing in the fork and accessories.
The Softail model line has multiple front fork configurations. They have had Springer leading link forks, reminiscent of the sprung front-ends that were used before the Hydra-Glide in 1949; the FXST designation is used for 21" front wheel bikes or when the Springer fork is used with a 21" wheel, while the FLST designation is used for 16" front wheel bikes or when the Springer fork is used with a 16" wheel. Because Softail models do not have rubber-mounted engines, they have more vibration in Evolution-engined Softails than in rubber-mounted Touring or Dyna models with Evolution engines. To compensate models used a counterbalanced version of the Twin Cam engine instead of the regular Twin Cam engine used in the Touring and Dyna models; the Twin Cam was replaced by a variant of the Harley-Davidson Milwaukee-Eight engine for the 2018 model year. Bill Davis, an avid Harley rider and engineer from St. Louis, designed the softail in the mid-1970s, his first design, which he worked on in 1974 and 1975, had a cantilever swingarm pivoted at the bottom and sprung at the top with the springs and shock absorber hidden under the seat.
Davis built a prototype based on his 1972 Super Glide. He patented the design and arranged to meet Willie G. Davidson August 1976. Davidson was impressed, but made no commitments, six months said Harley-Davidson was interested but would not use the design at that time. Davis continued to develop the design, switching the pivot and the springing points around so that the springs and shock absorber were under the frame and the pivot point was at the top of the triangular swingarm; this allowed the traditional Harley-Davidson oil tank to be placed under the seat. Davis attempted to produce the new design independently as the Road Worx Sub-Shock, but the partnership he had put together for this purpose collapsed. Harley-Davidson executive Jeffrey Bleustein contacted Davis shortly afterward and began negotiations to buy Davis's design. Davis sold his patents and tooling to Harley-Davidson in January 1982. After further testing and development, Davis's design was introduced in June 1983 as the 1984 Harley-Davidson FXST Softail.
In April 1980, Harley-Davidson started work on its own rear suspension design that would have the look of a hard-tail motorcycle. The job was given a low priority until in the year it was transferred to Jim Haubert Engineering, a firm that Harley-Davidson contracted yearly to custom build motorcycles and prototypes. Haubert built a prototype using his own rear suspension design that followed the look of the earlier Harley rigid frames; this version was completed enough for review by Harley-Davidson in January 1981. In 2017, Harley unveiled a redesigned Softail frame for the 2018 model year, the first major change since the introduction of the Twin Cam engine in 2000; the 2018 Softail frame uses a differently shaped swingarm suspended by a single rear shock absorber, mounted undermeath the seat in a similar fashion to the original Haubert and Davis designs. Harley claims that the new chassis is stiffer and lighter than the previous-generation Softail and Dyna platforms, the latter of, discontinued with some of its models being carried over to the new Softail chassis.
The 2017 Street Bob 103 ci was dyno made 65 hp and 88 lb ⋅ ft at the rear wheel. The new 2018 Street Bob 107 ci makes 101 lb ⋅ ft at the rear wheel; the 114 ci motor such as in the 2018 Heritage Classic produces 81 hp and 108 lb⋅ft at the rear wheel. The Softail is the most popular Harley-Davidson model family for heavy customizing and is used for show bikes. Many aftermarket manufacturers around the globe have specialized in Softail parts & accessories like wheels, fenders or tanks to change the look of the custom motorcycle. Harley-Davidson started an Inspiration Gallery to show their latest factory custom parts on all new models - many have their origin in CVO Softails, which are handmade Limited-Editions of the regular models. Other softail-style motorcycles: Honda VT600C Kawasaki Vulcan 800, 900 Suzuki VL 1500 Intruder LC / Boulevard C90 Victory Vegas Yamaha DragStar 650 and 450 Yamaha Royal Star, Royal Star Venture Yamaha XV1600A Yamaha DragStar 650, 950, 1100 Zero Engineering Type 9 Bicycle suspension List of Harley-Davidson motorcycles Cruelworld Softail at Von Dutch Kustom Cycles