Diesel motorcycle
A diesel motorcycle is a motorcycle with a diesel engine. With a traditionally poor power-to-weight ratio, most diesel engines are generally unsuited for use on motorcycles which normally desire low weight, compact size, high RPMs and rapid acceleration. In the 1980s, NATO forces in Europe standardized all their vehicles to operate with diesel fuel. Some forces had fleets of motorcycles and trials were conducted with diesel engines on these. Air-cooled single-cylinder engines built by Lombardini of Italy were used and had some success. This led to some countries re-fitting their bikes with diesel engines.
In 2005, the United States Marine Corps adopted the M1030M1, an off-road motorcycle based on the Kawasaki KLR650, and retrofitted it with an engine designed to run on diesel or JP8 jet fuel. Since other U.S. tactical vehicles like the HMMWV utility vehicle and M1 Abrams tank also use JP8, adopting a scout motorcycle which runs on the same fuel would ease logistics.
Further development by Cranfield University and California-based led to the production of the Kawasaki KLR650 based motorcycle for military use. The engine of this motorcycle is a liquid-cooled, single-cylinder four-stroke which displaces 584 cc.
In India, motorcycles built by Royal Enfield could be bought with 325 cc single-cylinder diesel engines because diesel fuel was much cheaper than petrol at the time, and of more reliable quality. These engines were noisy and unrefined and not very popular because of lower performance and higher weight penalties. The engines were originally designed for use in commercial applications such as electric generators and water pumps.
As of December 2006, several companies produce diesel motorcycles. More recently is .
Conversions
A popular conversion choice is to put an industrial diesel engine single or twin cylinder in a modified frame of a Royal Enfield from India.An alternative is to use industrial diesel engines or diesel engines from small cars. Frames are modified or completely self-built.
Production vehicles
Sommer Diesel 462
produces the Sommer Diesel 462. It is powered by Bavarian Hatz Diesel. The Sommer-diesel motorcycle is assembled by hand in small batches in Eppstein. Some components of the wheels and gears may be supplied by Royal Enfield of India. The frame was built in Germany and has been improved from the old one.Track T-800CDI
Track T-800CDI has an 800 cc three-cylinder CDI common rail turbo diesel engine developed by Mercedes and used in the Smart and a number of other products including hovercraft. Track runs an ECU especially for the motorcycle. It has a cardan shaft drive. The transmission is a Continuously Variable Transmission. The throttle is connected with an electronic throttle control. Dutch E.V.A. Products BV started to sell the diesel motorcycle in 2009. At the end of 2012 E.V.A. Products BV has gone into hibernation. Production has come to a halt. An estimated 50 motorcycles have been put on the road.The picture is of a prototype motorcycle.
Royal Enfield
Royal Enfield in India was the only manufacturer that has built a diesel motorcycle in mass production in the year of 1980s.An industrial diesel was installed in the frame of the British-based Royal Enfield. However, due to pollution laws, this bike is no longer produced. Initially street mechanics were mounting this engine in used Bullets, like retro Royal Enfield Bikes, with the 350 cc retrofit engine. On seeing the success of these bikes; Royal Enfield started manufacturing Bullets with the diesel engine and named it the Taurus. The Taurus was available with an electric starter in 1993.With competition getting intense, India's oldest motorcycle manufacturing company, Royal Enfield, is exploring newer segments, with the idea of bigger engines and diesel variants. Enfield is planning to bring diesel-powered bikes back into the Indian market, a project for which work is on.
Sooraj 325cc Diesel
A Saharanpur-based company, Sooraj Automobiles produced Diesel motorcycles with the 4-speed Albion Royal Enfield gearbox fitted with Italian Lombardini 325cc Diesel engine. The company advertised fuel efficiency of 86kmpl, and most of them are still in running condition. The chassis of the Sooraj was a unique design and manufactured by Sooraj Automobiles themselves with much thicker heavier gauge than the Royal Enfield chassis. The fork angle of the Sooraj's chassis was much steeper forward than that of the Royal Enfield's, which provided comparatively better balance and turning ergonomics to the Sooraj. It used 19 inch wheels similar to the Enfield with thick wide edged mudguards along with double cam drum brakes. It was the first Motorcycle in India to come with a Self-start and Direct fuel injection Diesel engine, much before the Enfield. The Sooraj Diesel 325cc motorcycle was very strong, sturdy and reliable which gave good competition to the Royal Enfield Diesel by eating up a huge amount of Enfield's sales at the time as it was much cheaper than a Royal Enfield Diesel and more economic than an Enfield Petrol.Hayes Diversified Technologies M1030M1
After several years engine development at Cranfield University, the HDT M1030M1 has entered service. It is produced by Hayes Diversified Technologies, and it is based around a modified Kawasaki KLR650. Top speed is approximately 90 mph and fuel consumption is advertised to be at. M1030M1s have successfully taken part at the British National Rally and the Bonneville Speed Trials.The U.S. Marine Corps bought 440 of the M1030M1 model, under the name M1030M1 JP8/Diesel. The M1030M1E AVTUR/Diesel Military motorcycle is sold to British and European NATO countries. A version made for the civilian market, the D650A1 "Bulldog" was originally slated for release in March 2006, but due to increased military demand for the M1030M1, production of the civilian Bulldog has been delayed indefinitely.
In the Summer of 2010 at Eurosatory, a French defence contractor exhibition, HDT presented the HDT 1030M2 a major upgrade of their present HDT1030M1. The 1030M2 chief change is an upgraded 670 cc engine which has a multifueled capability and produced 20% more power, and through a patented technology called MAC-C1 enables the engine to use not only standard automobile gasoline and truck diesel fuel, but five major jet fuel types; and even the heavier vegetable oil based biodiesel. As of September 2010 no orders have been placed.
Faired and unfaired Hayes Diesel motorcycles won second and fourth place at the 2011 Mid-Ohio Craig Vetter Fuel Economy Challenge.