A New Nova?

A New Nova?

ROUNDUP

Does The Motor Co. have a secret V-Four in the works?

BRUNO DEPRATO

IT IS DOUBTFUL THAT VERY MANY people remember Harley-Davidson's ill-fated Project Nova. The R&D program, which was started in 1976, set out to create a platform to counter the high-tech, high-performance frenzy generated by the second generation of Japanese Fours setting the market on fire with unprecedented horsepower.

A range of two-, fourand six-cylinder engines based on a 60-degree Vee arrangement was proposed. Liquidcooling, double overhead cams and a short-stroke design would allow revs to approach 10,000 rpm and produce as much as 135 horsepower. The test mules that engineers built were 800cc V-Fours, developed with the assistance of Porsche to meet the demands of the 500 to lOOOcc market. At the time, Harley’s smallest-displacement engine was the lOOOcc Ironhead Sportster.

Unfortunately, the project was killed just when the checkered flag appeared to be in sight. After significant investment, testing and getting Nova to a near-production-ready state, parent company AMF back-burned development. That was its first death. HarleyDavidson was then purchased back from AMF in 1981 by a select group of employees. The new owners, like the previous one, had some hard decisions to make. Ultimately, the new air-cooled Evolution V-Twins that also were in development offered immediate profitability for the cash-strapped, debt-ridden company. Nova was quietly tucked

away in a dark corner and mostly forgotten.

Now Harley-Davidson is rumored to be working on a new V-Four engine.

It is unclear whether this engine is for use in traditional H-D products and/or for Buell. In either case, this is really big news and proves that The Motor Company is determined to expand market share with new products, even in troubled times.

Our overseas sources say cylinders of the

secret Four are set at 72 degrees, which is a good compromise between

a theoretically perfectly balanced but long and untidy 90degree layout and a compact and elegantly symmetrical configuration, such as a 45-degree design. To

reach a superior level of primary balance, each throw of the crankshaft is split in two sections; the axis of each is set 18 degrees off centerline, for a total offset of 36 degrees. The final result is a 72-degree V-Four as well-balanced as a 90-degree V-Four. To further cancel any residual vibration, a balance shaft has also been added.

Possible displacements are thought to range between 1300 and 1600cc, with bores expected between 86 and 89mm while strokes would range from a very short 55.5 to an intermediate 64.5mm. The combination of an 86mm bore with a 55.5mm stroke delivers a 1290cc Four expected to rev to 12,000 rpm and produce power numbers in the region of 170 horsepower. Big numbers by H-D standards, to be sure.

If the rumored project ever makes it beyond the conceptual stage (our sources at H-D would neither deny nor confirm existence of such a project), it could be one of the most important in Harley-Davidson’s history, primarily because it treads on new turf and breaks with tradition. U