Kawasaki W1 and 2 | Some history

Kawasaki W series

From Wikipedia, the free encyclopedia

Kawasaki W1, W2, W3


Kawasaki W1SS, a two-carburetor offshoot of the original W1. Note the brake pedal on left side.

Manufacturer Kawasaki Aircraft Industries, later Kawasaki Motorcycle & Engine Company

Also called Meguro X-650, Kawasaki 650 Commander, Kawasaki RS650

Parent company Kawasaki Heavy Industries

The Kawasaki W series is a line of motorcycles made by Kawasaki since 1965 that shares some characteristics of classic British vertical-twin standard motorcycles. Sold as a 1966 model in the North American market, the first Kawasaki W1 had the largest engine displacement of any model manufactured in Japan at the time. Kawasaki continues to build models of the W brand similar to the W1.

Antecedents: Meguro K series

In 1960 the Akashi-based Kawasaki Aircraft Company acquired an interest in the Meguro motorcycle company, which had obtained a license to produce a copy of the 500 cc BSA A7. Meguro had been Japan’s largest motorcycle manufacturer but in the late 1950s its models had become less competitive and it was short of money. Kawasaki’s investment enabled Meguro to launch its A7 copy as the Meguro K.

The BSA A7, Meguro K and their respective derivatives have an overhead valve (i.e., pushrod) straight-twin engine with a pre-unit construction architecture. All have a 360° crankshaft angle, which provides an even firing interval between the two cylinders but high vibration caused by the two pistons rising and falling together.

In 1963 Meguro was taken over one hundred percent by the new Kawasaki Motorcycle Corporation, which maintained the licensing agreement with BSA and continued to build the K model, but due to lubrication problems Kawasaki made engine modifications and the Kawasaki K2 entered production in 1965 with improved crankshaft bearings and a larger oil pump. Since the introduction of the K2, the Meguro K model has tended to become known retrospectively as the K1.

The K2 has a larger timing cover which distinguishes it from the model K and the BSA A7. Also the K2 chassis has a different rear subframe, fuel tank and side panels. These changes gave the K2 a typically conservative Meguro image, dissimilar to the original BSA A7.

In 1965 the K2 was enlarged to 624 cc to become the Meguro X-650 prototype, which was displayed at the 1965 Tokyo Motor Show. The X-650 then became in turn the prototype for the Kawasaki W1. For the new Kawasaki big bike, the traditional look of Meguro motorcycles was replaced with a sleeker fuel tank, sportier mudguards (fenders) and other details intended to appeal to export markets, especially North America.

The Society of Automotive Engineers of Japan (Japanese), includes the 1966 Kawasaki 650-W1 as one of their 240 Landmarks of Japanese Automotive Technology.



A10 Super Rocket
A10 Super Rocket with the three-rifles BSA logo on the timing cover.



The Kawasaki W1 is based heavily on the post-war, pre-unit construction, 650cc vertical-twin BSA A7 design inherited from Meguro, but as time passed, the Kawasaki and BSA designs diverged. The BSA A10 (aka Rocket) engine is an under-square design with a 73 mm (2.9 in) bore and an 84 mm (3.3 in) stroke, whereas the W1 inherited its 72.6 mm (2.86 in) stroke from the K2 engine, adding displacement by increasing the size of its bore to 74 mm (2.9 in). This slightly over-square (i.e., short-stroke) design favors higher engine speeds, while reducing stresses on the crankshaft. In addition, the new W1 had a one-piece pressed crankshaft assembly with ball bearings and one-piece connecting rods with needle bearings, significant improvements over the earlier BSA (and Meguro) engines that used plain insert type bearings and two-piece connecting rods. Even though the BSA and Kawasaki 650cc engines were mechanically different from each other, visually they gave very much the same impression.

Likewise, in the design of its twin-loop frame, as well as its overall styling, the W1 motorcycle was clearly influenced by classic British road bikes, including shifting with the right foot and braking with the left. From 1966 to 1968 W1 engines were built with a single 31 mm Mikuni carburetor (this is only feasible in a straight-twin with a 360° crankshaft angle). Starting in 1968, the W1SS with two 28 mm Mikuni carbs took the place of the original W1. Also in 1968, the W2 (aka Commander) emerged. The W2SS was a restyled W1SS with slightly more horsepower, and the W2TT was a high-pipe version with twin mufflers on the left side. Due to flat sales in North America the W2TT was discontinued in 1969, the W2SS ended in 1970, and finally in 1971 Kawasaki axed the W1SS.

The 650 remained popular in Japan, and although some were exported to Europe in the 70s, subsequent models were produced primarily for the domestic market. The penultimate model in the W series was the W1SA with stylistic changes, but most importantly with the gearshift lever on the left side and the rear brake pedal on the right side, which is the standard configuration for Japanese motorcycles. The final version was the 1973 W3 model (aka RS650) with upgraded suspension as well as twin disc brakes in front. W series production ceased in 1974.



As soon as the W1 was released, Kawasaki realized that even an improved version of the BSA A10 (itself already discontinued) was at a disadvantage against the newer and faster unit construction British twins, the BSA Spitfire and the Triumph Bonneville T120. The W1 also had to compete with other Japanese twin-cylinder street bikes, such as the Suzuki T500 and the Honda CB450. If the W1 was seen as being behind the times, then Kawasaki came back with a two-stroke engine that was clearly ahead of its time, the 1967 A7 Avenger with performance at least equal to the W1. The following year the W series (as well as the British bikes) faced a new competitor in a state-of-the-art twin from Yamaha, the XS650.

In 1968 the domination of the inline-twin engine for high-performance street bikes came to an end when Triumph Engineering developed an inline-triple engine for the BSA Rocket 3/Triumph Trident. The 1969 Kawasaki H1 Mach III with an inline-triple two-stroke, and the Honda CB750’s Inline-four engine into the bargain, foreshadowed the ascendancy of multi-cylinder engines. The W series engines were oil-tight and reliable, but by comparison they had low levels of performance with high levels of vibration, and were ultimately unsuccessful on the sales floor. At the same time that production of the W series was ending in Japan, Kawasaki came up with a formula for successful four-stroke street bikes in its Z series.


Descendants: Kawasaki W brand

Main articles: Kawasaki W650 and Kawasaki W800

Today’s fascination with retro style motorcycles began in 1989 with the Honda GB500 and the Kawasaki Zephyr, both first produced for sale in Japan as 400cc models.] These retro-bikes evoked nostalgia for classic motorcycles from decades earlier.[22] The Zephyr was made using the Z series inline-fours from the 1970s as a template. By the late 1990s Kawasaki was designing successors to the Zephyr series, based on even older generations of motorcycles with twin-cylinder engines. In 1999 Kawasaki released new retro-bikes, the V-twin Drifter and the vertical-twin W650. Unlike the 1960s W series, the 1999-2007 W650 had an up-to-date engine design very different from its ancestors, while holding on to the vintage British motorcycle look. The 2011-2013 W800 carries on with the W brand, and expands the range to include Cafe racer models.


  • “Kawasaki W1 to W3”. Kawasaki motorbikes a pictorial story. www.jarlef.no. Retrieved 1 August 2013.
  • “About the Company”. Kawasaki Motorcycle & Engine Company. Kawasaki Heavy Industries, Ltd. Retrieved 2 August 2013.
  • Scheibe, Winni. “Kawasaki W1”. Classic Motorrad (in German). www.classic-motorrad.de. Retrieved 2 August 2013.
  • “Akashi Works”. Kawasaki Motorcycle & Engine Company. Kawasaki Heavy Industries, Ltd. Retrieved 2 August 2013.
  • “Kawasaki 650-W1”. 240 Landmarks of Japanese Automotive Technology. Society of Automotive Engineers of Japan, Inc. Retrieved 1 August 2013. The 650-W1, which had the largest displacement of any Japanese motorcycle at that time, was intended as Japan’s strategic entry into competition with the world’s top-class machines from British makers.
  • “Kawasaki Motorcycle Identification Guide”. Classicjapcycles.com. p. 4. Retrieved 6 August 2013.
  • “Historic roots: Kawasaki’s original W”. Kawasaki Motorcycle & Engine Company. Kawasaki Heavy Industries, Ltd. Retrieved 1 August 2013.
  • Salvadori, Clement (September 2011). “Retrospective: Meguro Junior S3 250: 1957 – 1958”. Rider. Retrieved 3 August 2013. Meguro was also producing the biggest-bore motorcycles in Japan, 500 and 650 twins that copied British engineering, and a deal was struck in 1961, with Kawasaki gradually absorbing Meguro.
  • “W800”. Kawasaki Motorcycle & Engine Company. Kawasaki Heavy Industries, Ltd. Retrieved 1 August 2013. The W800, in both looks and feel, pays homage to Kawasaki’s legendary W1, the model that started a brand that spans 45 years.
  • “Kawasaki’s W800 retro bike is here in time for Christmas”.(404 error) News. Kawasaki Motors South Africa. Retrieved 1 August 2013. The Kawasaki W800 is recognisably a descendant of the Kawasaki W1 of 1967 that was in turn a licensed copy of the famous 500cc BSA A7 that dated back to 1946.
  • “1999 Kawasaki W 650”. Just Bikes. 28 April 2011. Retrieved 3 August 2013. The first new ‘W 650’ debuted in 1999, looking little different from its 1960s predecessor. The overall design was arguably even more ‘British’ than the original W1, looking like a modern Triumph Bonneville, even though the W 650 predated the release of the new Bonnie by a couple of years.
  • Falcone (25 March 2008). “Die W650-Ahnengalerie Meguro/Kawasaki”. Datenbank W650/W800 (in German). Homepagemodules.de. Retrieved 2 August 2013.
  • Brown, Roland (November–December 2005). “Kawasaki W2TT Commander”. Motorcycle Classics. Retrieved 2 August 2013. The 624cc engine’s Y-shaped right engine cover was larger than the BSA’s equivalent, hinting at numerous internal differences.
  • “Vintage Kawasaki Motorcycle Photos & History”. TheWorldOfMotorcycles.com. Retrieved 1 August 2013. In the early model years, Kawasaki used a mirrored ‘M,’ or ‘MW’ on its tank badge, indicating ‘Meguro Works.’
  • “Motorcycle Museum”. Corporate Kawasaki. Canadian Kawasaki Motors Inc. Retrieved 2 August 2013.
  • Scheibe, Winni. “Kawasaki W650”. Classic Motorrad (in German). www.classic-motorrad.de. Retrieved 5 August 2013.
  • Klawsuc, Phil. “The W Files”. Ann O’Rack Productions. Retrieved 7 August 2013.
  • Cholot, Jean Jacques (30 November 2010). “Kawasaki: de la Meguro à la W 800: histoire et images”. Caradisiac (in French). Car & Boat Media. Retrieved 3 August 2013.
  • Scheibe, Winni. “Kawasaki W1 und W2 Modellgeschichte”. “Winni”-Scheibe.com (in German). Winfried “Winni” Scheibe. Retrieved 5 August 2013.
  • Edwards, David (1 November 2009). “Retro Bike Hall of Fame”. Cycle World. Retrieved 10 August 2013. The first modern retro bike? Probably the Honda GB500, which first saw the light of day in 1989 but was obviously inspired by the great British Singles of the 1950s.
  • “Kawasaki Zephyr”. 240 Landmarks of Japanese Automotive Technology. Society of Automotive Engineers of Japan, Inc. Retrieved 10 August 2013. The Kawasaki Zephyr was developed at that time to be a machine that would be easy to use and enjoyable for everyone. The model became a trend-setter for the ‘naked bike’ boom of the 1990s.
  • Kunz, Dave (7 July 2013). “Retro-style motorcycles combine best of old, new”. KABC-TV/DT. Retrieved 10 August 2013. There are two primary audiences for the retro-style bikes: those who might have had one back in the day and would like to have another, and then there are people who weren’t around back in the day who love the early ’70s style.
  • “History”. (404 error) Kawasaki W650 World. Kawasaki W650 Enthusiasts’ Group. Retrieved 3 August 2013.
  • Hedge, Trevor (2011). “Kawasaki W800 Reviewed and Tested”. mcnews.com.au. Retrieved 8 August 2013. In 2011, thanks to a 5mm larger bore, Kawasaki have reinvented their machine and the W650 has grown to become the W800 and this time around Triumph should definitely sit up and take notice.
    Edge, Dirck (25 January 2011). “Kawasaki W800 Cafe Style Available in Japan”. MotorcycleDaily.com. Motorcycle Daily. Retrieved 10 August 2013. Pictured is the W800 Café Style, which has been announced for the Japanese market. Don’t hold your breath waiting for this bike to be available in the U.S., but we can admire it from afar.


External links



Sourced from elsewhere



Kawasaki W2 650SS


Make Model — Kawasaki W2 650SS

Year — 1968

Engine — Air cooled, four stroke, parallel twin cylinder, OHV

Capacity —  624cc

Bore x Stroke — 74 x 72.6 mm

Compression Ratio — 8.7:1

Induction — Mikuni VM31

Ignition  / Starting — kick
Max Power — 53 hp @ 7000 rpm

Max Torque — 5.7 kgf-m @ 5500 rpm

Transmission / Drive — 4 Speed / shaft
Frame — Tubular, double cradle

Front Suspension – telescopic

Rear Suspension – shocks

Front Brakes — Drum

Rear Brakes — Drum

Front Tyre  — 3.25-19

Rear Tyre — 4.00-18

Dry-Weight — 191 kg

Fuel Capacity — 15 Litres

Overview Classic-motorrad.de /




The history of the W1 can be traced back to 1960 and the early K1, a motorcycle developed by the Japanese motorcycle meguro. Meguro had first started producing motorcycles back in 1909 and had modeled the K1 on the English BSA A7 as a replacement for their single cylinder Meguro Z7.

It was early days, and most Japanese motorcycle manufacturers at the time were basically building bikes copied from American and European models, particularly in the large displacement categories.

For its day, the K1 was an advanced design and showcased modern-day manufacturing techniques with its Air-Cooled , 4-stroke, Twin OHV 496cc engine mounted in a double-cradle frame.

In 1960, Meguro Works entered into a business relationship with Kawasaki Aircraft Co.,Ltd., leading to a full merger in 1963. Therefore, although the K1 was developed and produced by Meguro, selling it was left to Kawasaki Motor Sales Co., the forerunner of Kawasaki Motorcycle Co.,Ltd. At the time, the Kawasaki engineers were so deeply engaged in the development of a 4-stroke engine for small cars that they had no time to develop a new motorcycle engine. But by the end of 1962 the four-wheel project had ended and some of these car engineers transferred to Meguro and tool over the project. There were two projects that the developers had to tackle: the SG (a single-cylinder 250cc OHV) and the K1.

For both projects, ex-Meguro engineers kept working on the task of chassis development, while the SG and K1 engines were developed by the ex-Kawasaki engineers. Since the K models were still in the transition stage from Meguro to Kawasaki, there were many problems associated with technology transfers and maintenance. However, work proceeded at the same time on development of a successor to the K1\ the new W1. At the time, sales objectives were concentrated on receiving orders for police patrol motorcycles intended for guard duties during the 1964 Tokyo Olympics. Since there was no time to develop a new engine, or even to remodel an existing one, there was no choice but to use the K1 model as it was. However, the engineers still wanted to overcome some basic design flaws in the K1 engine. Because the sales side wanted to maintain the impressive appearance and dignified look of the K1, it was decided to remodel the engine only, and in 1965 the remodel the engine only, and in 1965 the remodeled K1 was introduced as the K2. (The changes included increased oil pump capacity, improved crankshaft bearings, etc. The Y-shape cover, the distinctive feature of the W models, was adopted at this stage.)

However, both the K1 and K2still shared the basic weak points of the BSA A7. The K2 was exported to the US for a test in response to the expanding American market for 4-stroke motorcycles. Unfortunately, it was rejected for a lack of power.

The answer was the W1 which was developed as a large, high-performance, 4-stroke based on the K2. With this new model, the basic problems found in the lubrication system (already improved in the K2)and the weakness in the crank’s big end durability was solved by going to a built-up crank. But their was insufficient time to implement the intended changes in the valve train (making it an O.H.C.). As far as the frame concerned, the conventional tubular frame from the BSA A7 was used unchanged.

The frame building technology that Kawasaki inherited from Meguro was the quite advanced for its time, and most f the models following the K1 adopted tube frames because they were comparatively easy to make. Even though Kawasaki had developed a 4 stroke engine much earlier, the K1,K2 and W1 were typical 4-stroke motorcycle models for their day and were, so to speak, textbook models reflecting the then-current design and production technologies.

The W series entry into the US market was rather unsuccessful because it was too similar to the K models in basic structure and lacked a feeling or impression of being “new”. The W models also mimicked too much the look of the BSA A7 for an American tastes, even though internally the engine was much improved from the BSA.

The W1 engine featured the larger bore of the K models and included a separate primary drive and transmission. The frame welding techniques came directly from the K models. Prior to the W1 Kawasaki only sold 2-strokes on the US market, but with the debut of the W1 it joined Honda in becoming one of the first Japanese motorcycle manufacturers to produce 4-strokes. While Honda had produced only 4-strokes from the beginning, Kawasaki’s entry into the US the market was based on predictions of increased sales for large displacement 4-strokes in the near future.

The 624cc engine of the W1 was one of the first large-displacement Japanese motorcycles.

However, the way motorcycles were used in America was quite different than expected and the W1 was found “unsuitable” for the American market. On the other hand, in Japan it was well received and became famous for its unique OHV vertical twin sound and individual style.


Sourced from elsewhere


In 1960, Kawasaki Aircraft acquired an interest in the Meguro motorcycle company. Meguro, which was once Japan’s largest motorcycle manufacturer, held a license to copy BSA’s 500cc A7, which it produced as the Model K.

W! engine

When Kawasaki took over Meguro entirely in 1963, it continued production of the motorcycle, refining it in 1965 with a stronger lower end and better lubrication as the K2.  In 1965, the K2 was increased to 625cc to become the W1. Styling was improved as well, to appeal to the North American market.

The W1 is commonly thought to be a copy of the 650cc BSA A10.  This is not the case.  In its evolution from the K to the K2 and the W1, a short stroke design was adopted.  The Kawasaki has a bore of 74 mm and a stroke of 72.6 mm, whereas the BSA A10 is a long stroke engine with dimensions of 73 mm x 84 mm, giving the engines different acceleration and running characteristics.W1 engine

The motorcycle was updated again in 1968 to become the W2 Commander,  then again in 1972 to become the W3.  Production ended in 1975.  By this time, the old British-base design was totally eclipsed for performance by many newer motorcycles, including Kawasaki’s own Mach III and Z1.

These motorcycles have become very desirable collectibles, and good examples are rare.  With their “old school” lines and chrome fenders and tank panels, they are more attractive than many other Japanese  motorcycles of their era.  Or at least this opinion has emerged over time.

The cutaway engine used for our quiz is owned by collector and fine motorcycle  broker Somer Hooker, of Brentwood, Tennessee.



W1 Rebuild

W1 Bobber