BMW K1
Encyclopedia
The BMW K1 is a motorcycle
that was designed by BMW
as a high-speed sports-tourer, designed to change the motorcycle media and buying public's mind of BMW as only a manufacturer of flat-twin tourers.
Based on the previously introduced BMW K100
, the K1 was designed for comfortable high-speed autobahn cruising at speeds of up to 150 mph (241.4 km/h). The radical aerodynamic design was a seven piece glass fibre structure, creating a world class leading drag coefficient
of 0.38. It was mated with a stiffened chassis, that included a single sided Paralever swingarm, design to stop shaft drive induced pitch and dive under heavy acceleration and braking, the first use of this on a K-series bike.
Although expensive and either loved or hated, and with some of its early technology either working in use or not—the enclosure created excess heat, while the long wheelbase created a 22 ft (6.7 m) turning circle—the short production run created the result that the motorcycling press and public never had the same view of BMW motorcycles again.
legislation on emissions regulation, BMW had started to develop an alternate technology to its traditional flat-twin engines with the introduction of the 1,000 cc BMW K100
from 1983 to 1992. Led by Josef Fritzenwenger and Stefan Pachernegg, the team developed a design based on a liquid-cooled Peugeot
car engine. In the base design of the K100, the engine was laid on its side in-line with the motorcycle frame, known as a longitudinal four, with the crankshaft on the right-hand side of the motorcycle, with the cylinders, pistons, camshafts, injectors and spark plugs on the left-hand side. This arrangement keeps the centre of gravity relatively low, which benefits handling.
to solve the problem.
In 1984 at the Cologne Motor Show, BMW design created the aerodynamic "Racer" mockup, based on a standard K100 chassis. At the 1988 Cologne show, the production K1 used the same large and all enveloping two-piece front mud guard mated closely to a seven-piece main fairing, that included two small panniers. The resultant drag coefficient
was 0.34 with the rider prone, the lowest of any production motorcycle in 1988.
Adding to the "different to traditional BMW" nature of the bike, the colour scheme of bright red or blue with yellow graphics and highlighting was bold, and hence seen as so different to normal BMW, bizarre.
Retaining the K100’s engines dimensions of 67 millimetre, the K1 was BMW's first 16-valve engine, using four valves per cylinder, with the camshafts acting directly on the bucket tappets. Other improvements over the K100 included higher compression pistons, lighter conrods and a 1.3 kg (2.9 lb) lighter crankshaft. This combined with digital Motronic
engine management system resulted in a 10 hp gain over the K100, producing 100 hp at the crankshaft at 8,000 rpm; and increased torque of 74 lbft versus the K100’s 64 lbft.
The stronger tubular steel chassis was mounted on wide 17 inches (431.8 mm) FPS front wheels, 18s in the back, with low profile radial tyres. The rear suspension was a Bilstein shock absorber
acting on a single-sided Paralever swingarm, which pushed the wheelbase out to 1565 mm (61.6 in). On the front were twin 41.7 mm (1.6 in) Marzocchi forks. The brakes were four-pot Brembo
over two-pot on the K100, with a pair of 305 mm (12 in) drilled discs. An Anti-lock braking system
was optional in all markets except North America, where it was standard.
The all over fairing was found in early press road tests to create excess heat below 50 mph (80.5 km/h), and in some cases burn riders. BMW eventually offered an under-fairing heat blanket which reduced this considerably, but it was always a problem. However, as BMW knew weight was a problem, the panels were well engineered but thin and subject to cracking. Resultantly panel fit was poor on early models, and combined with panel cracking earned the bike the nickname
"yoghurt carton" in Germany. The design and manufacture of the panels never changed in the bikes production, but the colouring schemes were toned down from a ketchup
red and metallic blue with yellow details, to a metallic black.
The engine, although well developed, suffered from secondary vibration. This was minimal in the three-cylinder K100 derived K75
, and minimised in the K100 through introduction of well designed vibration suppression. On the sporting inspired K1, the engine was directly mounted onto the frame, which led to secondary vibrations problems at certain mid-range engine revolutions.
In the important United States market, emissions regulations dragged the power out down to 95 hp. At almost US$13,000 it was also expensive, and when compared to the competition the excess price did not offer a sufficient performance or quality gap for volume sales. In comparison, the Honda CBR600F
was as fast and lighter, yet was almost two thirds of the price.
By 1993, the market had changed and developed considerably, with the introduction of sports bikes like the Tadao Baba
designed Honda Fireblade
, brought about the end of production. However, although it only sold 6,921 units, the K1 helped BMW change its persona forever with the press and market perception as simply a touring motorcycle manufacturer. It remains one of their most memorable machines.
Motorcycle
A motorcycle is a single-track, two-wheeled motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions.Motorcycles are one of the most...
that was designed by BMW
BMW Motorrad
BMW Motorrad is the motorcycle brand of the German company BMW, part of its Corporate and Brand Development division. The current General Director of the unit is Hendrik von Kuenheim....
as a high-speed sports-tourer, designed to change the motorcycle media and buying public's mind of BMW as only a manufacturer of flat-twin tourers.
Based on the previously introduced BMW K100
BMW K100
The BMW K100 is a family of four-cylinder 987 cc motorcycles that were manufactured by BMW from 1983 to 1992.-Background:As the 1970s came to an end, BMW faced three problems from developing its flat-twin boxer engine further:...
, the K1 was designed for comfortable high-speed autobahn cruising at speeds of up to 150 mph (241.4 km/h). The radical aerodynamic design was a seven piece glass fibre structure, creating a world class leading drag coefficient
Drag coefficient
In fluid dynamics, the drag coefficient is a dimensionless quantity that is used to quantify the drag or resistance of an object in a fluid environment such as air or water. It is used in the drag equation, where a lower drag coefficient indicates the object will have less aerodynamic or...
of 0.38. It was mated with a stiffened chassis, that included a single sided Paralever swingarm, design to stop shaft drive induced pitch and dive under heavy acceleration and braking, the first use of this on a K-series bike.
Although expensive and either loved or hated, and with some of its early technology either working in use or not—the enclosure created excess heat, while the long wheelbase created a 22 ft (6.7 m) turning circle—the short production run created the result that the motorcycling press and public never had the same view of BMW motorcycles again.
Background: solution to a marketing problem
Through the need to meet proposed European UnionEuropean Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
legislation on emissions regulation, BMW had started to develop an alternate technology to its traditional flat-twin engines with the introduction of the 1,000 cc BMW K100
BMW K100
The BMW K100 is a family of four-cylinder 987 cc motorcycles that were manufactured by BMW from 1983 to 1992.-Background:As the 1970s came to an end, BMW faced three problems from developing its flat-twin boxer engine further:...
from 1983 to 1992. Led by Josef Fritzenwenger and Stefan Pachernegg, the team developed a design based on a liquid-cooled Peugeot
Peugeot
Peugeot is a major French car brand, part of PSA Peugeot Citroën, the second largest carmaker based in Europe.The family business that precedes the current Peugeot company was founded in 1810, and manufactured coffee mills and bicycles. On 20 November 1858, Emile Peugeot applied for the lion...
car engine. In the base design of the K100, the engine was laid on its side in-line with the motorcycle frame, known as a longitudinal four, with the crankshaft on the right-hand side of the motorcycle, with the cylinders, pistons, camshafts, injectors and spark plugs on the left-hand side. This arrangement keeps the centre of gravity relatively low, which benefits handling.
Design
However, the K100 was still a cruiser/tourer design in bias, and BMW marketing wanted a sports orientated tourer to appeal to a more youth orientated market perception, and compete with the Japanese factories. BMW was committed to the manufacturer imposed 100 bhp limit for motorcycles sold in Germany, so decided that to address both issues it needed to turn to aerodynamicsAerodynamics
Aerodynamics is a branch of dynamics concerned with studying the motion of air, particularly when it interacts with a moving object. Aerodynamics is a subfield of fluid dynamics and gas dynamics, with much theory shared between them. Aerodynamics is often used synonymously with gas dynamics, with...
to solve the problem.
In 1984 at the Cologne Motor Show, BMW design created the aerodynamic "Racer" mockup, based on a standard K100 chassis. At the 1988 Cologne show, the production K1 used the same large and all enveloping two-piece front mud guard mated closely to a seven-piece main fairing, that included two small panniers. The resultant drag coefficient
Drag coefficient
In fluid dynamics, the drag coefficient is a dimensionless quantity that is used to quantify the drag or resistance of an object in a fluid environment such as air or water. It is used in the drag equation, where a lower drag coefficient indicates the object will have less aerodynamic or...
was 0.34 with the rider prone, the lowest of any production motorcycle in 1988.
Adding to the "different to traditional BMW" nature of the bike, the colour scheme of bright red or blue with yellow graphics and highlighting was bold, and hence seen as so different to normal BMW, bizarre.
Engineering
The K1 differed from the K100 in engineering terms, being designed for high speed and hence with many components either replaced or upgraded.Retaining the K100’s engines dimensions of 67 millimetre, the K1 was BMW's first 16-valve engine, using four valves per cylinder, with the camshafts acting directly on the bucket tappets. Other improvements over the K100 included higher compression pistons, lighter conrods and a 1.3 kg (2.9 lb) lighter crankshaft. This combined with digital Motronic
Motronic
Motronic is the trade name given to a range of digital engine-management systems developed by Robert Bosch GmbH, commonly known as Bosch.-Motronic ML1.x:Motronic ML1.x was one of the first digital engine-management systems developed by Bosch...
engine management system resulted in a 10 hp gain over the K100, producing 100 hp at the crankshaft at 8,000 rpm; and increased torque of 74 lbft versus the K100’s 64 lbft.
The stronger tubular steel chassis was mounted on wide 17 inches (431.8 mm) FPS front wheels, 18s in the back, with low profile radial tyres. The rear suspension was a Bilstein shock absorber
Shock absorber
A shock absorber is a mechanical device designed to smooth out or damp shock impulse, and dissipate kinetic energy. It is a type of dashpot.-Nomenclature:...
acting on a single-sided Paralever swingarm, which pushed the wheelbase out to 1565 mm (61.6 in). On the front were twin 41.7 mm (1.6 in) Marzocchi forks. The brakes were four-pot Brembo
Brembo
Brembo S.p.A. is a manufacturer of automotive brake systems, especially for high-performance cars and motorcycles. It was established in Bergamo, Italy in 1961. Soon after the company was formed, it specialised in disc brakes, which were exclusively imported from the United Kingdom at the time...
over two-pot on the K100, with a pair of 305 mm (12 in) drilled discs. An Anti-lock braking system
Anti-lock braking system
An anti-lock braking system is a safety system that allows the wheels on a motor vehicle to continue interacting tractively with the road surface as directed by driver steering inputs while braking, preventing the wheels from locking up and therefore avoiding skidding.An ABS generally offers...
was optional in all markets except North America, where it was standard.
Marketing, sales and usage
By the time the K1 was launched, it was quick but not fast. The result of the addition of the aerodynamic bodywork and general upgrading of engineering and components added to the weight, which as a result came in as heavy for a sports bike at 234 kg (515.9 lb). Combined with the extended wheelbase which created a 22 feet (6.7 m) turning circle, it made the bike an economical and comfortable sports tourer. But the engine was not powerful enough against the weight to make the bike quick accelerating, and hence sports-competitive.The all over fairing was found in early press road tests to create excess heat below 50 mph (80.5 km/h), and in some cases burn riders. BMW eventually offered an under-fairing heat blanket which reduced this considerably, but it was always a problem. However, as BMW knew weight was a problem, the panels were well engineered but thin and subject to cracking. Resultantly panel fit was poor on early models, and combined with panel cracking earned the bike the nickname
Nickname
A nickname is "a usually familiar or humorous but sometimes pointed or cruel name given to a person or place, as a supposedly appropriate replacement for or addition to the proper name.", or a name similar in origin and pronunciation from the original name....
"yoghurt carton" in Germany. The design and manufacture of the panels never changed in the bikes production, but the colouring schemes were toned down from a ketchup
Ketchup
Ketchup is a sweet-and-tangy condiment typically made from tomatoes, vinegar, sugar or high-fructose corn syrup and an assortment of...
red and metallic blue with yellow details, to a metallic black.
The engine, although well developed, suffered from secondary vibration. This was minimal in the three-cylinder K100 derived K75
BMW K75
The BMW K75 was a standard motorcycle produced by BMW Motorrad from 1985 to 1995. At the time of its introduction, the K75 was BMW's cheapest motorcycle...
, and minimised in the K100 through introduction of well designed vibration suppression. On the sporting inspired K1, the engine was directly mounted onto the frame, which led to secondary vibrations problems at certain mid-range engine revolutions.
In the important United States market, emissions regulations dragged the power out down to 95 hp. At almost US$13,000 it was also expensive, and when compared to the competition the excess price did not offer a sufficient performance or quality gap for volume sales. In comparison, the Honda CBR600F
Honda CBR600F
The Honda CBR600F, known as the 'Hurricane' in the US market, is a sports motorcycle made by Honda from 1987-1990, with an all new model of the same name released in 2011. The original CBR600F was Honda's first inline four-cylinder, fully faired sport bike. It had a liquid cooled DOHC 16-valve...
was as fast and lighter, yet was almost two thirds of the price.
By 1993, the market had changed and developed considerably, with the introduction of sports bikes like the Tadao Baba
Tadao Baba
Tadao Baba is a retired Japanese motorcycle engineer, the original designer of the Honda Fireblade.-Career:Baba joined Honda Motorcycles from High School in 1962, aged 18 - the company itself was only 14 years old. Working in the machinery section, he made crankcases and cylinder heads for Honda’s...
designed Honda Fireblade
Honda Fireblade
The Honda Fireblade is a family of sport motorcycles manufactured by Honda since 1992. The first model was designed by Tadao Baba.*CBR900RR, 1992–1995*CBR919RR, 1996–1999*CBR929RR, 2000–2001*CBR954RR, 2002–2003...
, brought about the end of production. However, although it only sold 6,921 units, the K1 helped BMW change its persona forever with the press and market perception as simply a touring motorcycle manufacturer. It remains one of their most memorable machines.