The Benefits of a V Motorcycle Engine


Greater performance has been the relentless quest for manufacturers and riders since the start of the wonderful era of motorcycling. The first motorcycle had just one cylinder but the V-twin followed hard on its heels. The obvious reason is that, with the axis on the crankshaft across the frame, you can have twice the engine cylinder capacity and performance for very little increase in width. A narrow engine is very important on a motorcycle because you have to bank over to go round bends without being tipped off by touching the engine on the road. A narrow motorcycle is also desirable to keep the frontal area small for lower wind resistance.

To me a wide motorcycle is an anachronism and although you could cite the Honda 250 straight-six as an extremely successful machine, it was only 250cc and therefore had only little cylinders to stack across the frame. The most elegant engine ever made, at least in my opinion, was the Moto Guzzi V8, for its width was only 30mm wider than its world championship winning Bialbero 350cc single. Of course, Moto Guzzi also came up with its trademark arrangement with the cylinders protruding from each side of the motorcycle; this must be one of the longest running series engines, beginning its life in the 1930s as an agricultural.

The extra width of a V-twin engine of twice the capacity of a single cylinder is just the width of one of its con rods. Similarly, a V4 750cc is only wider than an equivalent 375cc parallel twin by the width of one of its con rods.

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The Lubrication of Combustion Engines


The lubrication of internal combustion engines began with the need to prevent moving parts from damaging each other. As one surface slides or rolls against another, extreme temperatures are generated in the very small regions in which the high points of one surface contact those of the other. Metals melt and fuse, forming micro-welds. These welds are broken by the further motion of the parts, generating surface damage and liberating wear particles.

Even a tiny amount of lubricant can prevent most of this by forming a film which separates the parts very slightly. This greatly extends parts life. One example is wheel bearings, which because they turn slowly and generate little heat can be lubricated by grease. Grease is a mixture of a soap, which provides structure, and oil, which is the lubricant. The gearboxes of many motorcycles through about 1935 were likewise lubricated by grease. As friction and parts motion generated heat, oil melted out of the grease to form lubricating films.

As machine parts move faster, the ability of grease to adhere to them disappears and oil must be conveyed to where it is needed in some other way. The earliest engines were lubricated by 'splash' - pouring a liter or less oil into the crankcase and allowing the motion of the rotating crank to throw it everywhere. Small guides were often cast into the inner surfaces of the crankcase to channel oil to holes that led to the main bearings. As oil made its way past piston rings and thence out of the engine, more had to be provided from a small tank by a hand pump. This was operated by a vigilant rider who looked back often. If there were no smoky trail, the engine needed a shot of oil.

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The Development of Cast Wheels


In motorcycle racing, horsepower, handling and tire performance have always been inextricably linked. And in the early '70s great leaps of performance were made in all these areas and this carried on into the '80s. Traditional twin-loop steel frames gave way to aluminum-spar chassis, power went over and above 100, then 120 and 140 horsepower, tires became slicks, slicks became Radials and so on.

One important part of the package, which had to work with all these changes and was crucial to them all, was the introduction of the cast wheel, during the '70s.

In 1975 Giacomo Agostini's title-winning Yamaha OW-23 featured cast wheels by the end of that season. With power heading upwards courtesy of the arrival of the two-strokes, wheel and tire design had to keep up. The 'traditional' spoked or laced wheel looked great, but like a biplane criss-crossed with rigging wires, it was fast becoming an anachronism.

In general terms spoked wheels needed attention on road and race motorcycle. You needed to check how tight the spokes were often, you had to keep them clean and free from rust and you had to run an inner tube. Cast wheels were tougher, maintenance free and became a fashion all of their own. In motorcycle racing circles aluminum soon gave way to magnesium as the material of choice, with the likes of Marvic producing their first three-spoke magnesium wheel in 1983 for Grand Prix racing use.

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Kawasaki Motorcycles and the Forgotten 50-years Celebration


This year marks a marked a major landmark in the world of motorcycles: it's 50 years since the first Kawasaki motorcycle was produced. That 125cc B7, a two-stroke single, left the company's factory at Akashi, Japan in 1961, starting a line that has included great motorcycles from the mighty Z1 four to the latest ZX-10R and which has led to sporting success for countless machines with the famous lime green paintwork.

However, if you haven't heard of Kawasaki's plans to celebrate half-a-century of motorcycle production, you're not alone. The total number of 50th anniversary events, publicity stunts, limited-edition models, even special paint schemes, do not exist! Rarely can such a significant landmark for a major global company have passed so unheralded.

To be fair to Kawasaki, there are good reasons for this. For one things, the company's early history is complicated and not very clear. Although the B7 of 1961 is officially regarded as the first-ever Kawasaki motorcycle, even some of the company's own literature has accorded the honor to the following year's B8.

Kawasaki also built motorcycles earlier, under a different name. In fact, an almost identical 125cc single. Called the Meihatsu New Ace, was assembled in the same Akashi factory in 1960. Kawasaki's entry into the two-wheeled world was, therefore, very different from that of the other Japanese marques. That first Kawasaki wasn't built by a tiny, newly created company, but by a giant corporation that had taken over an established firm. Whereas Honda, Suzuki and Yamaha began with motorcycles as their major, if not only, product, Kawasaki also produced ships and airplanes. Kawasaki had built Japan's first steam locomotive in 1901 and traced its history back to 1878, when Shoju Kawasaki has founded a shipyard at Tsukiji, near Tokyo.

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Yamaha’s Grand Prix history to shine in UK and France in coming weeks


Yamaha will see out the remaining weeks of a memorable 50th year of Grand Prix racing with a comprehensive display of their achievements and history on the track for British and French audiences.

Visitors to the Motorcycle Live Show in Birmingham and the Motorcycle, Scooter, Quad Show (Le Salon de la Moto) in Paris will be able to roll back the years and memories with the presence of the Yamaha Anniversary Expo; in the UK from November 19th-27th and in France from November 30th-December 4th.

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Harley-Davidson and its Custom Vehicle Operation


Throughout history, through good times and bad, Harley-Davidson have never missed an opportunity to further the brand. The success of their hard part and enormous motorcycle garment range are great examples of that. The Harley-David Custom Vehicle Operation (CVO) is another; perhaps the most extreme, of maximization of what is already a market leading brand.

From the very first day that a Harley-Davidson motorcycle rolled off the production line, now well over a century ago, owners have been showing their individuality on their bikes. Way back then the Harley-Davidson factory didn't even fit pillion seats as standard. Then some switched on character at the factory (or shed as it was then) recognized a chance to make an extra few Dollars by making and selling one as an official accessory. In double quick time Harley-Davidson realized this could be a very profitable side to their motorcycle business.

When Harley-Davidson were reinvented, with the '80s revival, was the time personalization really took off. In tandem wearing the Harley brand, regardless of whether you rode it or not, became fashionable. Be it myth, legend or fact, the story has it that hard parts and clothing made more profit for the brand than motorcycles, more than once in the company's history. By the '80s everyone wanted to be an individual, so why should Harley-Davidson owners be any different? The difference is they have never stopped wanting that individuality.

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The Yamaha XS1100 - The Big Boy Classic


The Yamaha XS1100 was Yamaha's answer to the ever-growing superbike cult of the 1970s. Honda started it back in 1968 and arguably Kawasaki and Suzuki jointly put a full stop on it come the turn of the next decade, with the Yamaha adding a bit of spice during the latter part.

The Yamaha XS1100 was a good sound engineering exercise in how a motorcycle should be built, its powerhouse engine was housed in a strong steel chassis with a titanic shaft drive keeping the horsepower in check as they were transferred to the rear wheel. The only trouble in the weight that all this overkill created, the Yamaha XS1100 is certainly no lightweight, especially when compared to its rivals and it showed when viewed alongside the opposition.

The type was a popular model in the USA however, where long roads span out for mile upon mile making the ow maintenance Yamaha a breeze to cruise the highways. Unlike the other big motorcycles, the engine was tuned to give massive spread of power and peaked around 8,000rpm, this allied to a wide and flat torque curve gave the rider a huge punch with each and every gear shift.

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The BSA B31 - Universal British Motorcycle


After we wrote an article about the Universal Japanese Motorcycle, an all purpose motorcycle that will perform almost any task. The discussion started with some emails which leaded to the question, was there a Universal British Motorcycle during the golden motorcycle age in the '50s? The answer is very likely, yes there were several.

One, however, represents like few others, the reliable British overhead-valve, medium-weight, single cylinder motorcycle of the 1950s. The 348cc BSA B31, although a post World War 2 model has its roots at the beginning of the war. The 1940 BSA catalog featured a 348cc Silver Sports B29. Only a handful of BSA B29's were built, and most of them went immediately into army service. The army then opted for side-valve models for the rest of the war. Production of the BSA B31 proper began in 1945. The BSA B31 lasted until the end of the '50s.

The BSA B31 is often overshadowed by its more glamorous cousin the Gold Star, but then sportsbikes tend to steal the limelight. In 1946 the trials model B32 followed the B31. In 1949 BSA produced the third version, a clubman type racer known as the B32 Special. This grew into the BSA B32GS Gold Star.

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The Universal Japanese Motorcycle


The universal Japanese motorcycle was an awkward situation for the Japanese motorcycle industry to find itself in during the early eighties. All four Japanese motorcycle manufacturers (Honda, Suzuki, Kawasaki and Yamaha) built motorcycles which were hard to distinguish from one another. They were all in-line DOHC fours with five-speed transmissions and twin-down tube, full cradle frames. Moreover, they all looked and sounded so similar they were collectively referred to as Universal Japanese Motorcycles.

Kawasaki decided to do something about this. What they came up with ultimately spawned the popular emergence of sportsbikes.

In addition to the flashy, bodywork, paint jobs and the all-black lower engine cases, which helped distinguish the original Kawasaki GPz from the rest of the pack, real attention was given to the motorcycle's handling capabilities. It's frame was heavily braced and the steering-head area gusseted.

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The Start of the Modern Motorcycle


The motorcycle has been around for over 100 years, yet it's possible to look at machines form the first generation and see aspects still present in one form or another on our current motorcycles. But that doesn't mean there hasn't been any progress. There has. Lots of it...

Aluminum, steel and cast iron have all been used, but it's the little things that make the difference. Aluminum cylinders lose heat faster and more effectively than cast iron predecessors, and cast aluminum cylinders with water-cooling and plated bores are even better. But Yamaha took most of the '60s to learn how to get chrome bores to stay stuck on their two-stroke racers, their road motorcycles using cast iron liners for three decades.

Crankshafts used to be bolted together with roller bearing big ends, and ball and roller mains. Advances in machining quality, oil technology and bearing materials means 99% of new motorcycles are all plain bearings and high pressure oil, only a few designs now persevere with the old ways. Plain bearings allowed crankcases to be split differently – horizontally instead of vertically – to reduce oil leaks. Less metal was needed to support the new, more rigid bearings so engine weight dropped.

Computer design allows ultra-thin crankcase walls and calculates exactly where extra metal is needed. Advanced vacuum casting techniques mean metal can be put only where it's needed, allowing engine weight to drop even further.

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