Montesa Scorpion
CYCLE WORLD IMPRESSION
MOTORCYCLE manufacturers could be excused for adopting a love-hate attitude toward American enthusiasts. There are more than 2 million riders in this country, and they represent a wealthy, eager-to-buy market. But, oh, what worrying and head-scratching they must cause in design departments with their insistent demands for dual purpose street/trail bikes.
Any machine intended for this class is of necessity a compromise, and if a maker does not blend correctly the street and trail aspects of his product, it is in danger of being useless for both activities. Engine tuning, gearing, brakes, suspension, tires-a hundred items must be designed to cater both for freeway cruising and mountain tracks.
One result of these compromises is that some bikes are built almost like scramblers, while others tackle the off-road part of their work in a more lighthearted manner. The Montesa 250-cc Scorpion is in this latter group. It is a delightful bike for the man or woman who enjoys an easygoing trip into the backwoods or the desert. The hardnosed rider whose soul is happy only when his bike is broadside in a comer, engine screaming and rear wheel thrashing, will prefer one of Monte sa’s scramblers.
The Scorpion is a handsome machine, and lacks the angular appearance possessed by many trail machines. Light gray frame, red fuel tank and rear fender, Akront alloy rims, and a very smart Telesco front fork contribute to its good looks. Drilled, chromeplated parts are becoming almost a trademark of Montesa machines. On the Scorpion they are used to locate the headlamp and front fender. The rear brake pedal likewise is drilled. A steering lock is operated by the same key which opens the tool compartment.
The bike is powered by an engine rated at a' mild 21 bhp. The word “mild” is used purposely-in comparison, the identical engine in the Scorpion’s big brother, the LaCross scrambler, is tuned to develop 30 bhp. The Scorpion does lack the power which would take it into the top class of crosscountry machinery. Coupled with a lack of torque at the bottom end of the rpm range, this often makes hard work for the rider.
For example, pulling away on any kind of loose surface requires more engine revolutions than should really be necessary with this size of bike. Also, when test riders attempted steep climbs, they were occasionally surprised to find the Scorpion needed a down change to, perhaps, second gear, when third gear should have been sufficient for the hill.
Montesa lessens this problem somewhat by offering a wide range of gearing for the Scorpion. The test machine had a 12-tooth countershaft sprocket and a 42-tooth rear sprocket. But customers can order countershaft sprockets from 12 through 16 teeth, and back sprockets with anything from 40 to 60 teeth. Anyone who plans a lot of trail riding with a Scorpion should ask for a rear sprocket at least several sizes larger than the standard 42 teeth. The standard arrangement, with a 12-tooth countershaft sprocket, gives first gear a ratio of 21.42:1, which is sometimes a little too high for the Scorpion’s engine to handle.
Customers also can order tires of their choice. CYCLE WORLD’S test bike was equipped with a 3.50-19 Pirelli front cover, with a studded roadster tread pattern, and a 3.50-18 Avon Trials Supreme on the rear. The Scorpion will accept tires up to 4 in. wide in universal pattern, and up to 3.50 in. wide in knobby styles.
Montesa Scorpion
An Easygoing Fun Bike
The engine is an ultra-short stroke unit. Stroke is 60 mm, while bore is 72.5 mm. Piston, cylinder barrel and head are of aluminum, while the shrunk-in liner is of cast iron. A caged roller bearing is used at the bottom end of the steel connecting rod, and a needle bearing is fitted at the small end.
Primary drive is by helical gears; the multiplate clutch is mounted on the gearbox primary shaft. The clutch is a sturdily-designed unit that would appear easily capable of transmitting the Scorpion’s power output. There are six driver plates and seven driven plates, running in an oil bath, and six springs. The entire package is contained in a steel gear wheel which runs on double-row ball bearings. The result is light, positive action on the clutch lever.
Backbone of the frame is a rolled steel tube forming a full single loop. The Scorpion has in-built protection against rock damage to the engine, in the form of two smaller diameter tubes which run from the downtube to the top rear suspension mounts. This means that no less than three tubes run underneath the engine. This is not all; the tubes are linked by two steel plates-one on either side of the main tube—extensively drilled for lightness. With all that surrounding armor, it is very unlikely that the Scorpion’s sting could be blunted by even the largest of rocks.
The rear swinging arms pivot on elastic bushings. Rear suspension units are by the Spanish Telesco company—like the front fork-and have two-way damping, and five position load adjuster cams for the springs.
Rider comfort is well provided for. The large black seat is more than 10 in. wide and 4 in. deep, and has plenty of space for two people. The handlebars sweep well rearward to provide a riding position almost like that of a California “desert sled.” This makes for relaxed riding on both road and trail. The handlebar grips are the type with a pattern of many small rectangular ridges, which offer about as much grip as it is possible to exert on the bars. The rider’s footrests are folding, but not spring-loaded. In hard cornering, with the foot stuck out into the dirt, the rest can easily be flicked up by a bush or long grass, and the riders must blindly push the rest back down.
A fat exhaust pipe and expansion chamber adequately quell engine noise. The rear frame tube on' the left side actually bends outward in a semicircle to allow the expansion chamber room. This unusual treatment of an important frame member has no ill effect on handling, and even gives the exhaust system added protection in the event of a crash.
Quality of the welds and general finish on the Scorpion is high, and on the test bike was marred only by a small area of chrome flaking off the handlebar. Also, during a tough test period, the speedometer vibrated loose in the headlamp, a footpeg and the rear lamp vibrated off, and the air cleaner unscrewed itself.
On the road, the Scorpion is pleasant if not sensational. The brakes, 7 in. in diameter front and rear, cope with sudden halts better than the anchors on many street/trail bikes. The front unit has twin leading shoes; a single leading shoe is used at the rear.
Montesa now has an excellent range of off-road machines, with the Scorpion lining up beside the 250-cc LaCross and 360-cc Cappra GP motocross models, and a new 250-cc trials bike soon to be announced. ■
