Cycle News - Archive Issues - 1980's

Honda's 1985 CR500RF features several visual changes over 1984 model. Below, new engine apparently uses many parts from current CR. CR forks are works Showas; rear end has new shock and link for more travel. (Below) Frame and running gear are mostly unchanged. The pre-production motocrosser, the only one of its kind in Australia, is under evaluation by Honda Australia for final de- Report from Australia Handa's CRBDDRF water-cooler revealed The first water-cooled 500cc motocross bike seen in Australia was raced to victory in its debut on July 8 when Jeff Leisk won an open 16 meeting' on a Honda CR500RF. vf';lopment of the 1985 production bike. Honda in Japan has issued several variations of the machine around the world for testing and feedback before it decides on the final specifications of the RF model. Team Honda Australia race manager Clyde Wolfenden is confident the engine in Leisk's new bike is very dose to what will appear in the production model, but the frame and running gear is yet to be sorted. In the World 500 Motoccross Championship, which has five Hondas in the top six places, there are variations being raced by the HRC team. Andre Malherbe and Erik Geboers, first and third in the championship respectively, are mounted on "preproduction" 1985 mod.els, while Dave Thorpe and Andre Vromans, fourth and fifth overall, ride 1984 "factory" bikes. The differences are the sprockets, carburetors, rear sub-frame tubing (round on the works bikes, and square on the preproduction models), and the works bikes' hydraulic clutches. The Hondas use a lot of alloy in the frame and engine, but the works Kawasakis and KTMs are lighter. The model bei ng raced by Jeff Leisk, the current Mr. Motocross Series points leader, is probably only cosmetically different to what will be the production bike, according to his mechanic, Gary Benn. The new engine is 49lcc and is totally redesigned; nobody's telling what bore and stroke are, and it's unknown whether or not the RF shares any internal engine parts with the RE. Some observers think bore and stroke are unchanged. Twin radiators are mounrf'd on the front down tube, holding 1.8 quarts of coolant. The engine's water pump is mounted on the lower front of the right-hand side of the motor, and it is driven directly off the primary gear. Apparently the majority of the internals mirror the CR500RE specifications. The five-speed gearbox has the same ratios and the same reed valve/inlet manifold from the RE is fitted. The carburetor is a 36mm Oat-slide Keihin, breathing through a larger single foam element air filter. The engine has a centered exhaust port, and the expansion chamber has been reshaped to clear the radiator. The aluminum muffler is fixed to the pipe and not to the detachable subframe as was the case on the RE. The frame is a single downtube item that splits into a double cradle to dear the exhaust pipe at the motor. The forks on Leisk's bike are works Showa units, while the rear Showa shock has a larger body for greater oil capacity to make it run cooler and less susceptible to fading. The new ProLink linkages mean the shock travel is less, but they amount to the same rear wheel travel. The shock therefore does not need to be compressed as much to get the same rear wheel travel. The hock is still adjustable for compression and damping changes. The brakes, hubs, spokes, rims, rear brake pedal and cable appear the same as the RE units. Other changes include new blue fork gaiters, new blue spring on the shock, new Pro-Link graphics on the swingarm, a thinner seat at the rear, with new CR graphics. A detachable throttle housing means it is possible to change the throttle without removing the whole assembly. The fuel tank holds 2.5 gallons, but this and the radiator cowlings are likely to change. The scoops are clear red plastic, and the tank molding had many imperfections. The mudguards are the same as the RE's. but the side-

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