Report From Japan
REPORT FROM JAPAN
JACK YAMAGUCHI
YAMAHA 90 SPORTS HX
The new version of Yamaha’s ultra-lightweight street sports model is called the 90 HX. It features the same overall design as its bigger brothers of the series. And as compared with its forerunner HS 90, overall length has increased to 74.4 in. from 72.0., and dry weight is up from 195.8 lb. to 209.0 lb.
Other features include a newly-designed black-coated aluminum cylinder, and fins and crankcase like the 250-cc DX and 350-cc RX.
1 he fuel tank can be tilted up on its side for the sake of easier inside maintenance, and frame tubes under the fuel tank have been made one-piece for the improvement of torsional ruggedness.
YAMAHA 125 AT2 TRAIL
Yamaha’s ultra-lightweight trail model, the 125 A12, has also been fully modified. The focus of these modifications is the newly developed seven-port, reed valve engine which Yamaha calls its “torque induction” powerplant. In this engine, the intake port acts as an additional scavenging port to improve the function of the tormer five-port sca venging system. Yamaha has already applied for the patents of this unique system in eight countries including Ja pan, the United States and West Ger many.
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SPECI F ICAT IONS Engine . . . 2-stroke. Displacement Bore x stroke . Compression stroke -Max. power Lubrication Starting system - . Transmission Overall length Overall width Overall height Wheelbase Mm. ground clearance Weight Fuel tank capacity 7-port, reed valve Single 123cc 56x50mm 7.1:1 - - l3bhpat7000rpm Autolube Primary kick or electric - 5-speed constant mesh 78.40 in. 36.40 in. 43.60 in. 51.40 in. 9.0 in. 206.8 lb. 1.6gal.
VAN-VAN FROM SUZUKI
Suzuki is now offering its new RV90 all terrain cycle, called the Van-Van in the home market. As Honda's unique three wheeler is reserved exclusively for the American market (it cannot be registered in Japan, failing to meet several legal requirements), the Van-Van is the first of its kind in which the fun loving Japanese can sink his yen.
The Van-Van is quite straightforward in its general layout, and looks like a blown and beefed-up mini-trail. The power unit is a combination of a K90-based aluminum single-cylinder engine displacing 88ec. It develops 8 bhp at 6000 rpm and has a four-speed gearbox with a conventional hand-operated clutch. The bike sports gigantic Bridgestone 6.70-10 tires, designed for low air pressure. The Van-Van comes complete with a hand air pump and a pressure gauge as standard accessories.
The Van-Van attains a top speed of 40 mph on paved surfaces with good acceleration, thanks to lowish gearing. It is quite at ease pottering around town, or commuting to a nearby sand dune. It features respectable lighting equipment and an effective braking system. For an equivalent of about $300 as delivered in Japan, il is a remarkable multi-purpose bike.
SUPER BIKE SCENE
Disc front brakes are in. Honda is going all out installing this anchoring system on its extensive 250-and-up machines. Yamaha will follow suit with the 650 Twin.
Kawasaki will soon have its own superbike. No, not the much rumored “1300 V-4”—it’s been shelved. And, not a 650 version of the Mach III. According to industry rumor mills, this is due to an unwritten agreement among Japanese cycle makers that no member should invade the sacred Harley-Davidson domain. It’s not that they are afraid of the potence of the Milwaukee Twin, but that they do not want to push its maker. The U.S.-Japan trade relationship is strained tight enough. My informant suggests a more sober 750-850 Kawasaki, and if I may quote Kawasaki’s outspoken Terry Yamada, “We would go four-stroke for anything over 650.’’
Suzuki’s GT750 water-cooled Three is now a reality, and the Japanese buyer is getting an unusual preference in picking up one. (His U.S. counterpart may have to wait as long as six months before its debut.) And, a Wankel rotary engined prototype is progressing well at Hamamatsu. Suzuki’s original plan was to launch the first Wankel cycle in the spring of 1973, but since then, the project has been considerably sped up.
In February this year, four development engineers were dispatched to West Germany to obtain necessary knowhows. On their return to Japan, these four men worked with zeal and enthusiasm, developing a water-cooled Twin tandem rotor engine with a chamber capacity of 500cc (equivalent to a lOOOcc normal piston engine). 1 gather Suzuki is aiming at January 1972 for its release of the first Suzuki Wankel cycle.
HELMET LAW
From May 1972, it will become mandatory in Japan for motorcyclists to wear helmets when riding motorcycles with engine capacities of over 50cc on all types of roads. At the moment, cycle riders are required to wear headgear when they are traveling on our toll expressways.
