special forces blaze a trail with modified motorcycle
The Jordanian Special Operations Command (SOCOM) has taken into service an unusual all-terrain motorcycle originally designed by Rokon Inc of the US.
At the April 2000 SOFEX show in Amman it was announced that Rokon had signed a co-operation agreement with the King Abdullah Design and Development Bureau (KADDB) to develop heavy-duty, dual-wheel-drive, off-road motorcycles for Jordan and other countries in the Middle East and North Africa. A modified version of the basic design, designated AB23 Desert Ranger, has since been devised by KADDB in association with Rokon to meet local military operating requirements.
An initial batch of four Trail-Blazer motorcycles was supplied by Rokon to enable the user to commence extended trials and evaluation prior to formal acceptance of the AB23 Desert Ranger, anticipated for March 2001. KADDB and Rokon completed their own development and trials program in October 2000 and have since been preparing for industrialization of the Desert Ranger at the KADDB facilities in the King Hussein Main Workshops, Jordan. It is understood all Desert Rangers intended for supply throughout the Middle East and North Africa will be manufactured and supported from Jordan by KADDB, which plans to display the vehicle jointly with Rokon at IDEX Abu Dhabi in March.
Rokon president Thomas Blais told IDR that, pending the start of Jordanian production, the company remains the only producer of such dual-wheel drive motorcycles, which are built for traction in mountainous terrain rather than speed. The engine is coupled to a three-speed automatic torque converter located under the seat behind the engine. This acts as a transfer case, delivering drive to the rear wheel via a chain, and to the front wheel via a shaft that runs through the backbone of the frame and then onto a chain. On both outputs from the transfer case there is a mechanical disc brake. A clutched coupling enables the front wheel to freewheel when the handlebars are turned off-center so as not to hinder maneuvering.
The first 2x2 motorbike was produced in the US over 45 years ago, and was initially aimed at hunters and recreational users. However, numbers of Rokon motorbikes have since also been supplied for use by US special forces in the Vietnam and Gulf wars, and to the Brazilian special forces.
The baseline model is powered by a 10hp 146cc Chrysler two-stroke engine driving through a three-speed automatic transmission, but the AB23 Desert Ranger mounts a Kohler, 172cc single-cylinder, four-stroke, fan-cooled petrol engine, which delivers 6.6hp at 4,000rpm. According to Blais the fitting of the four-stroke engine makes the Desert Ranger quieter in operation than any quadbike or all-terrain vehicle. The top speed in the high-speed range is just under 72km/h, and gradient capability is 60º.
The main fuel tank carries 10 liters of gasoline/oil mix, sufficient for 500km or six to nine hours of operation, but an additional 9.4 or 17 liters may be carried in each of the two auxiliary fuel tanks located in each drum-wheel. In desert operations it is expected one of the drum-wheels would instead be used for water storage, the additional weight in the wheels helping to improve traction. The Desert Ranger's dry weight is 94.3kg (Trail-Blazer, 84kg), and the sealed wheel hubs in combination with low-pressure tires enable it to be floated across deep water obstacles. The Desert Ranger can ford to a depth of 61cm and has a ground clearance of 38cm.
Its low dry weight enables the Desert Ranger to be carried on vehicles such as the AB3 Black Iris or the AB5 special forces' LandRover as a scouting adjunct, or for when gradients, soft going or path-widths prevent normal four-wheel drive movement. Accessories include a power take-off kit to drive pumps and generators in the field, a tow bar, and a sidecar to carry up to 500 lb (226kg) of additional equipment.
Jordanian special forces test Rokon dual-wheel-drive motorcycles.
The AB23 variant, co-developed with KADDB, is designed to give motorized
access to otherwise inaccessible observation points. It is self-floating,
and can be carried on a light mother vehicle. Its sealed wheel hubs
may be used to stow supplementary fuel and water for several days
of autonomous operation.
The Jordanian Special Operations Command is the third client for Rokon
dual-wheel drive motorbikes, the first two being the US special forces
and Brazilian special forces.
View of the AB23 revealing a good view of the front-wheel drive mechanism.