Making Sense Of The Yamaha Niken, A Motorcycle With Two Front Ends

What this controversial three-wheeled, 847cc triple is, and what it is not

Yamaha Niken MT-09
Are three wheels better than two? One reason for poor motorcycle tire grip is that a cambering vehicle can present only roughly one-third of its tread width to the pavement, while a car can present 100 percent at all times.Yamaha

Yamaha's Niken is a motorcycle with zero roll stiffness, meaning that it leans to go around corners, is controlled like a motorcycle, and, unlike Piaggio's MP3 scooter, cannot stand up by itself when stationary. It just happens to have two front wheels quite close together, permitted by a contrivance of rocking beams and multiple joints to allow the vehicle to lean normally; lock up of the rocking beams is said to occur at 45 degrees of lean. The rear of the machine is based upon the three-cylinder MT-09.

Yamaha calls such machines “leaning multi-wheel” (LMW) vehicles, and its work with such things began in secret in 1977, using its Passol two-wheeled scooter as an experimental base. A photo from that time shows a trike with two front wheels, supporting above them a large wire shopping basket.

For me, the presence of the shopping basket unfortunately brought to mind BSA’s Ariel 3 scooter, a project developed from 1967 and launched in ’70 with two upright rear wheels and a lean-to-turn single front wheel. Planned and tooled for 2,000 units per week, it had sold a few hundred by the time of BSA’s closure in ’73.

On-board instrumentation showed that grip was smoothly transferred from the low-grip wheel to the high-grip wheel without steering upset.

At the 2007 Tokyo Show, Yamaha displayed the Tesseract, described as “four wheels but a motorcycle” because it too displayed the zero-roll rigidity now offered in Niken. Yamaha’s research had shown this four-wheeled vehicle operated just as a motorcycle does, using the same rider skills. The word “tesseract” describes the four-dimensional analog of a cube.

In 2014, Yamaha showed another LMW, this one called Tricity, a 125 billed as a city commuter. During the research behind these projects, Yamaha made an interesting discovery: If its leaning trike ran one of its front wheels over pavement of low grip while the other front wheel ran on pavement with normal grip, on-board instrumentation showed that grip was smoothly transferred from the low-grip wheel to the high-grip wheel without steering upset. This is the research behind the claim that Niken provides superior front grip to that of a conventional single front motorcycle wheel.

Niken GT sport-tourer
Front unsprung weight of the $15,999 Niken and $17,299 Niken GT sport-tourer (shown) is high, but Yamaha has tried to reduce it somewhat by using 15-inch wheels. Racing motorcycles suffer in turning ability by comparison with race cars because they have so little rubber on the ground.Yamaha

While considerations of unsprung weight—of which Niken has nearly twice as much up front as does a conventional bike, despite its twin 15-inch wheels being notionally lighter individually than a conventional bike’s single 17-incher—would suggest that over unsmooth surfaces the dual front end would offer less grip, Yamaha seems to be saying that by “sampling” the pavement in more than one place, Niken’s dual front end may in a statistical sense find enough grip to remain stable when conventional bikes might not, particularly on rough pavement, in the presence of liquids, or across sand or gravel.

Here is the gist of Niken: It is an experiment to determine whether motorcycle sales could be expanded by offering greater safety via provision of automotive-like features. As I’m sure is obvious to the reader, this is risky business because it seems to imply that conventional motorcycles are unsafe.

Yamaha Tricity 155
The Yamaha Tricity 155 debuted at the 2017 Tokyo Motor Show. Patents for leaning-wheel machines reach back as far as 1869. Al Fonda, an associate of flight-test expert Bill Milliken, built a leaning-wheel kart that he called the HyPhy Tilting Trike. There was also the Ariel 3, into which BSA poured 2 million pounds.Yamaha

Niken is complex, and it is heavy. Each front wheel (the two are 16 inches apart) has its own pair of fork tubes, and the rocking beams, pivots, and steering linkage that join them to the chassis and harmonize their steering have 100 pounds extra weight and occupy space. All this takes some getting used to, so we all await with interest the conclusions reached by experienced road-test people.

A bit of reading reveals leaning-wheel vehicles are described in more than 400 patents dating back to 1869. In 1923, the great Freddie Dixon and passenger T. Walter Denney easily won the Isle of Man Sidecar TT on a “banking sidecar outfit.” In Germany in the 1930s appeared research into “camber thrust,” an apparently mysterious ability of a cambered (leaned) wheel to generate thrust in the direction of the camber. Because the outside of the footprint travels a larger circle than the inside, a twisting force appears that “steers” the footprint (tending to steer the front end along with it) onto a curving path.

MWT9 concept
Yamaha referred to its MWT9 concept as "Cornering Master." All of these odd vehicles swim upstream against the appealing basic simplicity of the motorcycle. Like the various complex recumbent bicycles, they may have specific advantages. But as complex as they are, they cannot hope for a large market.Yamaha

Since then, a tremendous number of leaning-wheel vehicles have been conceived, built, and tested, and for which many wonderful claims have been made. In 1960, for example, Al Fonda at Calspan (a research/testing group near Buffalo, New York) built the HyPhy Tilting Trike described in the autobiographical book Equations of Motion by controllability researcher William Milliken. Between 1981 and 2005, a number of Hannes Myburgh’s Flexit banking sidecar vehicles were built, some under license in the US. Leaning wheels just keep coming back.

Tesseract
The hybrid Tesseract was fitted with "dual-scythe suspension." Yamaha claims that, “Zero roll rigidity makes the basic vehicle dynamics of a four-wheeled motorcycle identical to those of a conventional motorcycle.” This is why the Niken has to be held up; it has no roll resistance built into it.Yamaha

Another familiar historical phenomenon is the periodic conviction by the motorcycle industry that poor sales could be boosted if only their products were more like cars: cleaner, quieter, safer, more convenient, and with a higher social image (no rockers, racers, or oil-stained tinkerers need apply). This was a constant chant heard in Britain during the Great Depression and was acted upon by several makers in the immediate postwar years. Vincent built its fully enclosed Black Prince; no gears, cams or linkages were visible, just gleaming, squeaking fiberglass panels. The Sunbeam brand was affixed to a vibrating fat-tired design that appealed to very few. Velocette, its reputation based on production of sporting roadsters, decided to bet the farm on a liquid-cooled and underpowered thing called the LE, which appealed mainly to Her Majesty’s postal service.

The results of those experiments, if history is a guide, have been products that make the motorcycle unrecognizable to most people.

In the 1980s slump, Honda’s marketing consultants theorized that a population of well-dressed, well-heeled buyers existed for whom there was no motorcycle clean, quiet, or convenient enough to trigger purchase. The result was the mega-scooter known as Pacific Coast. It was said to have found some buyers in the Netherlands. And remember the craze for “lockable storage,” a concept that was once expected to ignite sales among hip downtown folk?

What do these experiments suggest? First, they show the motorcycle industry does take up arms against a sea of troubles—eras of poor sales, such as the present or 1929–’35—and try to come up with really different new product that may have fresh appeal.

Second, the results of those experiments, if history is a guide, have been products that make the motorcycle unrecognizable to most people (Yamaha’s forkless GTS1000, Sunbeam’s S7, Honda’s Rune, etc.) and tend to end up on special programs by which the dealer gives the unsold machines to a nearby trade school in return for certain considerations. The public thinks it knows what a motorcycle should look like.

One final point: The great fundamental strength of the motorcycle is its simplicity. Yes, simplicity has been violated by adding suspension, engines with more than one cylinder, and electronic rider aids. But, basically, the motorcycle remains two wheels, an engine, and a place to sit. Let us praise Yamaha for seeking to expand the idea of what a motorcycle can be and wish it success with Niken.