Specialty motorcycle manufacturer Viper Motorcycle Co. reports it is taking delivery of a series of redesigned, short-stroke engines for its 2011 Viper models. The Illmor-designed 152-in. engine is described as the largest, most powerful air/oil-cooled production V-twin engine available.
Minnesota-based Viper Powersports designs and manufactures V-Twin Super Cruiser motorcycles, V-Twin aftermarket engines, and related aftermarket products. Its joint-venture partner, Ilmor Engineering, provides technical developmental support for the proprietary 152-cubic inch Viper V-Twin engine.
Nesbitt indicates that the Illmor joint venture will allow it to expand as an OEM, providing a proprietary product designed and manufactured by Viper/Ilmor.
The 2011 Diamondback 152 is scheduled for shipment this month. A second model, the Mamba, and also powered by the Ilmor 152, is scheduled for introduction this summer.
Terry Nesbitt, Viper president, details that the new engines and drive case parts “are CNC machined from 6061 aluminum billet alloy. Each component piece is then hand-polished by American craftsmen prior to assembly.”
Nesbitt explains that, in addition to overall increased performance, the new engine produces considerably less vibration and runs cooler due to the improved oil flow throughout the engine via an Ilmor-designed twin scavenge dry-sump oiling system. Peak torque is an industry first massive 153 foot-pounds."
Paul Ray, President, Ilmor Engineering Inc., stated: "We have hundreds of hours of dyno testing resulting in a powerful, dependable, EPA-certified high-mileage engine. This is a Viper proprietary engine with state-of-the-art technology. The Ilmor air/oil dry-sump scavenge system utilizes three oil pump stages. The first stage is for oil feed with twin stages for independent drainage of the heads and crankcase, greatly improving overall oil flow. Our unique system provides much needed cooling to the cylinder heads, well beyond conventional air-cooling resulting in greater reliability. The Viper/Ilmor crankshaft uses an oversize crank pin for durability and has a unique balance formula to dramatically reduce vibration levels."