Ossa 230
OSSA 230
CYCLE WORLD ROAD TEST
THIS STREET-AND-ROAD OSSA seems more hare than bear. To put it another way, riding a 230-cc Ossa Wildfire in no way is related to the management of a big beast; this small, well-mannered rabbit of a machine is the closest many people ever will get to the finely balanced feel of a road racer.
A safe forecast is that once some of these aforementioned riders straddle the Ossa Wildfire, they'll fit fairings, extended seating, and other apparatus in order to, indeed, go road racing.
Swift and nimble, the Wildfire is the fleet-footed offshoot of an ursine family, a bunch of Spanish bears, namely the Ossa Pioneer, a multi-purpose street/bush machine; the Ossa Stiletto (CW, Aug. '67), assembled to suit the scrambles enthusiast; and the Ossa Plonker, expressly for the observed trials competitor, and available only on special order.
The test Wildfire arrived in its shipping crate, which was eagerly pried open. Fitting handlebars and footpegs, levers and cranks was a matter of less than an hour's work.
Gasoline and oil were mixed at 20:1, the tank was filled, and fuel taps were turned on. Three firm kicks brought life to the two-cycle single-cylinder powerplant. The machine was eased around the block four times or so. Then, just as the Ossa's performance and handling characteristics were whetting appetites for some open road touring work, the engine quit — dead. Subsequent inspection showed the fire delivered to the engine's spark plug was anything but wild.
A half day's fiddling brought no success. The Wildfire was trucked to a shop for repair. Diagnosis was that the Ossa's unit coil/transistor assembly had failed. A just barely loose wire in the magneto circuit was responsible for the difficulty. A drop of solder secured the wire; a new ignition coil/transistor unit restored spark to the engine.
The major point of this discussion is that the Ossa, through a very minor, one-in-a-million fault, managed to get off on the wrong foot. Prejudice against the little Spanish rabbit developed before it could be given a fair run. Later, during extensive trials, the Ossa Wildfire redeemed itself, erased certain predispositions, and totally reversed a jaundiced view to healthy enthusiasm. This certainly is no mean feat for a motorbike which, during repeated — and fruitless — efforts to bump-start its dead engine, thoroughly exhausted a broad vocabulary of poolroom oaths.
Once running, the Ossa Wildfire was called upon to prove itself, perhaps to a greater extent than are machines which aren't initially perverse.
Proof starts with visual inspection. Silver frame and tank paint are accented with bright crimson and gold trim, striking in this day of candy apple blue or red, or black motorcycles. Buffed stainless fenders, front and rear, complement the plated handlebars and levers. The seat is upholstered in plain black vinyl, and fitted with a passenger grip strap of like material. Detracting somewhat from the overall businesslike harmony of the Wildfire are a too small, very inaccurate, almost unreadable speedometer/odometer, integral with the headlamp housing; and a plastic chain guard. A more readable, more accurate speedometer, and addition of a tachometer would greatly improve the desirability of the machine; and the chain guard should be fabricated of stronger material, something less affected by vibration.
Contributing to the Wildfire's general aura of fleet transportation are the machine's hand-aligned-at-the-factory frame and suspension. The frame, a single top tube, duplex cradle unit, is welded of seamless tubing. Suspension is comprised of Telesco hydraulically damped front fork of 4.75-in. travel, and rear swinging arms with integral 3-in. travel coil springs and shock dampers, also by Telesco.
The Wildfire's brakes, components shared with Stiletto, Pioneer and Plonker models, are leading and trailing shoes in 158-mm diameter drums, front and rear.
The outstanding feature of the Wildfire, as with the machine tested earlier, is the boxy, oversquare 230-cc engine. Though the powerplant offers nothing esoteric in engineering, it displays numerous features representative of the best in current two-cycle engine design and practice. Underneath the polished diecast aluminum cases are caged roller bearings for the big end, and a flywheel press fitted at 15 tons. Within the squared fins of the alloy cylinder barrel, the iron liner contains a tapered piston, designed to expand to a cylindrical shape at engine operating temperatures for closer tolerances and greater power delivery. Ossa practice is to mount the piston pin in needle bearings.
Ossa transistorized ignition, of Motoplat manufacture, is fitted to the Wildfire, as it is to other machines among the bears. Timing is through a flywheel sending unit, rather than breaker points, and spark voltage is developed within the unitized coil/transistor assembly.
Carburetion on the Wildfire is through an IRZ double needle unit of 32-mm mixing chamber diameter. Though thoroughly discussed in the earlier Ossa road test, this component, variants of which are fitted to the other three machines of clover leaf marque, is worthy of brief review. The carburetor features two nozzle/needle systems, one for low to mid-range operation, the other for high rpm duty, and a single slide with a divided choke. The choke is horizontally partitioned by a vane cast into the carburetor body. Spray nozzles extend through the bottom of the choke, with the high speed nozzle orifice located just above the partition. When the slide is up to 50 percent open, only the low range needle/nozzle supplies fuel for mixture with inducted air. The partition separates the high speed orifice from the air stream until the lower edge of the slide passes the partition. At this point, the second needle starts delivery of additional fuel to the engine. Though in description carburetion appears to be a two-stage function, its effect is one of unbroken accelerative smoothness from low end to top engine speed of approximately 7000 rpm.
The latter rpm produces a seemingly conservative 25 bhp, which is delivered to the rear wheel through a duplex primary chain, multiple wet clutch and a rather conventional drum shift four-speed gearbox.
From the rider's standpoint, the Ossa Wildfire seems a small machine, close-coupled on its 51.6-in. wheelbase. The Wildfire's shortness, seat height, handlebar width, and footpeg locations induce a comfortably erect riding position for through-town trickling, but prevent an equitable road riding crouch for all save the shortest riders.
On the road, away from city traffic, the Ossa bear/ rabbit enters its own element, the swoops and bends of back-country asphalt and concrete. Touring power and rpm range are more than expected of only 230 cc, a displacement with which the Ossa easily is the equal of some 250-cc machinery.
However/power isn't the main consideration in road riding with the Ossa Wildfire. Handling, the Ossa's nimble ability to take the line of the rider's choice through a series of short radius bends, and the machine's inherent keen balance, make fast riding a pleasurable experience.
Judicious gear selection, accomplished with quick, positive, short strokes of the change lever, permit engine speed to be maintained at approximately 5500 rpm (a guesstimate), which seems fairly comfortable and somewhere near the powerplant's torque delivery peak. Changes to maintain this rpm become a matter of reflex, rather than of conscious effort, a procedure accomplished as though the Wildfire is equipped with a Detroit-style automatic transmission.
The Ossa Wildfire will attract buyers who know something about riding motorcycles — buyers who won't make the purchase on horsepower claims alone. ■
OSSA 230 WILDFIRE
