Cycle News - Archive Issues - 1970's

; Once upon a time, when a Honda == CL-72 was the hot set-up, a dual ~ purpose bike was one you could ride to and from your favorite g = dirt. Since then the market has exploded like a yeast colony in a clay crock full of sugar water. Now the American dirt rider is so jaded that almost no compromise in the way of street-ability is acceptable on a serious dirt bike . The Spanish were largely responsible fo r this jading effect ; "t: now it is the Spanish who are redefining 0.. the term "dual purpose dirt bike." It began unofficially around 1968-70 , ~ with private owners fitting I.S.D.T. kits to their Matadors, or bolting -Stiletto top ends to their Pioneers, then running the result in everything from enduros to hare scrambles to motocross.' Bultaco made th e trend a factory eff o rt by creating the Alpina o u t of Sherpa T parts with a dash of Matador for flavor . Now Ossa has created the Explorer. Like the Alpina, it is developed fro m the parent company's trials model, but leans more heavily in the trials direction than the Bultaco. Mechanically, it is a Mick Andrews Replica with a big tank, a fat seat, superfluous buddy pegs, and a few other detail differences that gently bend its trials behaviour toward the needs of the non-specialized dirt rider. Visually, it is a fairly pleasing motorcycle, especially viewed from a short distance set in its own element. Close-up, you notice a certain graininess to the surface finish of the tank, and the stripe up the center of the tank is a rather crudely-applied decal. These, hopefully are early production-run problems, because the machine is otherwise well detailed in appearance. Our t est bike was fitted with" the l!rge enduro speedometer in the moun t familiar to Pioneer , owners, and the same infamous Leonelli handlebar switchbox that has been a plague on Spanish bikes since Year One. The folks who se t up the test bike were more co y than most. They disconnected the kill button entirely so the ignition wouldn't drop out the first time the switchbox got wet. Good thinking. In the plus colum n, the speedo has a resettable trip odometer, the fork breathers really breathe , (earlier ones didn't, on both Bultaco and Ossa), and the rubber headlight mounts are downright clever. The throttle 'c ab le is nicely booted against grit top and bottom an a cross-the-board improvement on all Spanish equipment comi ng in recently. The direc t AC lighting equipment is no t street legal, and it's not meant to be . (The machine is placarded for off-road use only.) It was meant to get you back to camp when nigh tfall catches you au t in the boanies, and is well suited to that task. There's a pretty fair stone shield on ' the headlight and both ligh t s are rubber isolation mounted, so you're going to have to crash pretty spe ctacularly to put one of them out of commission. (We know .. . Ed.) , The toolbox is down in the side panel on the left, and the cover should come off only when you want it to. The tools themselves are state-of-the-art Spanish, including the little Barcelona speedwrench we have a particular fondness for . However, there was no tool in our kit that fit the rear axle nu ts. If this is a production oversight, it's a pretty grievous one, because the chain does stretch, and your buddy's Yamah a is not always handy to borrow tools from in the field. - So much for static walk-around and pre-flight servicing, at least for the moment. Starting drill when cold is S.O.P.; gas on, tickle, and prod. When hot, , j ust prod on ce. We religiously turned off the gas tap each time we shut it off out of old habit, but in all fairness to the machine, it really doesn't drool the cran kcase full like Spanish bikes used to . That's old hat. One staffer called the kickstarter awkward, and maybe it is, standing flatfooted beside the bike . It is far less awkward when you get yourself in an awkward position and have to rest art in - 24 the middle of a gully, straddling a huge rock, or precariously clinging to the side of one of SoC al's ohmuhgawd hills. At times like these, when your bod is so contorted that all you can manage is a half-hearted stab, a half-hearted stab is, all you need, due to the long throw 'an d high mechanical ratio of the "awkward" kickstarter , It's not like having primary kickstart, bu t at least somebody was thinking about the guy in borderline trouble when they designed the thing. It does spin the eng ine when you need it most. The Ossa was ridden off and on for several w eekends, trying it out on as many varieties of terrain as we could find in Southern California. (Testing an all-purpose d irt bike in th is area can be a bit co n finin g, at times. There are so many characteristic American soils we don't have ' - ' like Iowa mud, for example.) One t hing we feel that - affected all test impressions was th e choice of tires. The Pirelli MotoTrial covers fitted to our test bike were not the best choice. Both Yankee's Full Bore trials tire and Dunlop's 2-ply trials tire are far better. The Pirellis seemed to have too much sidewall stiffness and not enough tread stability. , Matter of fact, we question the fitting of trials tires out of the crate. The machine is not streetable, and trials tires generally are only required equipment for Expert/Master class trials riders who will co mp ete on specialized trials bikes anyway. The Novice/Amateur riders who will be most likely to compete in trials on an Explorer are allowed by . most sanctioning groups to 'ru n knobbies. (In fact, the Explorer would qualify for the Trailbike category at many events.) The Barum M-9/M-19 pattern tires used to work extremely well on Pioneers. They should also work well on an Explorer. Given the traction, the Explorer is almost unstoppable on a hill or on most other rough terrain. One staff rider, who also owns a Sherpa T, has never ridden a motorcycle that was more fun to climb hill s with. The only thing that stops the Explorer is lo ss of momentum due to wheelspin, which goes back again to the choice of tires. The way the chassis and engine work together under throttle at low to medium speeds is just outasight. The response at full throttle is almost like a charac ter istic signature. Reg ardless of the angle of terrain, up, down, or flat , the bike lifts the front wheel a stable four to six inches off the ground and grunts un til the engine runs ou t of wind. Then you shift and it does exactly the same thing all over again, un til you go for top gear . Then it's a lo-o -o-ng ratio step (see specs), so long Yha t you have to buzz hell out of it in fourth before it will pull top comfortably. This is typical trials gearing, a direct car ry -over from the M.A .R. Before you knock it, remember that's what accounts for the excellent performance in the rough cabby stuff where th is machine is most at home . With the 27mm carb, the power curve is that of a slightly asthmatic Pioneer, which, combined with the Explorer's 194 pound dry. weight, yields out-of-the-hole performance equal to or slightly better than the heavier Pioneer. The Explorer does most of the standard trials bike tricks and does them well . Steering while go ing picky-picky is very quick and precise as with itsspiritual ancestor, the M.A.R. It jumps logs, tracks well on loose roily rocks, grunts its way through deep sand with very good control (throttle-steers beautifully when executing a square turn in sand), and handles off-camber riding all righ t, though it has a tendency to track toward the low sid e that takes some getting used to. With all this going for it, it 's still not a serious trials bike. Even with the rather garish cutaways, the 2. 25 gallon tank gets in the way of the forks enough to require positive fork stops. This leaves the Explorer with less steering

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