DAKAR 1985 | Honda, magnesium for the engine!

The Hondas that took part in the Paris-Dakar are derived from the new XL 600 L Electric Starter, of which deliveries in Italy are starting in this period. In the racing version, however, it has been preserved, for weight matters, kick starter. The frame is the standard one with the rear part decomposable instead of fixed.

And’ the solution of the bolted rear has been chosen to allow a faster intervention on the suspension, the classic Pro-Link. The step is longer (1550 millimeters against 1410) to ensure greater stability at high speeds on desert tracks. The lengthening of the wheelbase was achieved by working on the front end and with the adoption of a longer swingarm.




The forks are aesthetically the same as those of standard, but have been modified both as calibration, with the adoption of springs suitable for the greatest weight, than as braking, with a different system of pumps inside. The monoshock is also modified in the calibration and braking system. The braking system is standard, with a disc at the front 240 millimeters and a double piston floating caliper.

Wheels are traditional (in the standard motorcycle, on the other hand, new concept wheels are mounted in which the radius has the fixing system on the hub instead of on the rim). Depending on the terrain, inner tubes or mousses were used. The engine has a special magnesium alloy crankcase, to save weight, while the cylinder is made of cast iron like that-the normal.




They have been prepared two versions, one of 591 displacement, the other of 630 (the standard engine is a 589). In the race was used the 591, for which Honda declares a power to the wheel of about 44 horses in 6600 RPM. In both versions we intervened both on the bore and on the stroke (97 x 80 and 100,3 X 80 against the 100 x 75 of the standard engine), and for-so the crankshaft was made specially. The camshaft is special, and offers the advantage of better use at low revs.

The compression ratio has been increased to 9 : 1 (from 8,6 : 1). The carburetors and the clutch are the standard ones, while a slightly shorter fifth ratio has been adopted in the gearbox. The air filter, composed of two normal sponge filters, is placed in the back of the tank. Under the seat, instead of the original filter, there is the additional tank of gasoline. The capacity is 32 litres for the main tank and 11 for the one under the saddle.




The fairing encloses the headlight and the oil cooler, an additional headlight is mounted next to it. The instrumentation, including the trip-master, is electronic.
La Honda, derived from the new XL 600 L Electric Starter, exploits fairly sophisticated technical solutions, like the magnesium alloy cast crankcase.

In the photos: the air filter at the back of the tank; the handlebar with the cassette for the "road-book" and the digital instrumentation; you can also see the additional headlight mounted on the side of the fairing.

Article taken from Motociclismo April 1985

  • Max666

    BRAVO for your excellent archival work !
    Honda Yamaha enthusiast since 1975 and Dakar since 1979

    • iron

      Thank you Max, nous en sommes passionnés et nous sommes heureux qu’il soit apprécié en France 🙂