Ossa 250 Six Days Replica
OSSA 250 SIX DAYS REPLICA
Cycle World Road Test
The Object Was To Combine The Best Of The Pioneer And The Stiletto, Put It Together In One Package, And Tack On The Name “Replica.” Ossa’s Six Days Team Copy, The One That Got Out Before It Was Ready.
OSSA’S PIONEER has always been one of our favorite machines for trail or enduro riding. They seemed to run forever, were not the slightest bit fussy, and had the pulling characteristics of an EMD locomotive. Trouble was, they hadn’t changed much over the last few years, save for a five-speed gearbox, and it was definitely time for an update.
But rather than revise the Pioneer, it was decided that a new model should be brought into the picture, one better suited and more ready for Enduro competition. With an Ossa team already on development bikes in the field, why not simply copy the result of their efforts? And, of course, that way they could tack on the name “Replica,” which is always good for a few additional sales.
The new Six Days Replica was designed to eliminate the few shortcomings of the Pioneer, specifically in the area of enduro use. Items such as more top end power, better high speed handling, and improved braking headed the list. If the Pioneer was good, the SDR just had to be a winner, and we had high expectations of it being just that.
Appearance wise, the SDR comes on like a Playboy Bunny in a railroad freight yard. It is one of the most striking dirt machines to come along in quite some time; but then again, Ossa styling treatments have a reputation for being somewhat unorthodox. The new model is an exercise in fiberglass sculpture, from front to rear.
A base color of white is impregnated into the fiberglass itself, but red accent bands and gold pin striping are painted on. Because the 3-gal. fuel tank is a plastic like material and very flexible, it will be much harder to damage than the front fender and rear tail section, which are true fiberglass. Both of these items are easy enough to replace, but they can be costly if they’re broken often.
By removing the knurled knob on the seat’s rear bracket, the padded unit can be slipped off the front retainer and removed. This will give access to a small tool compartment, as well as four 10mm bolts holding the plastic unit in place. Lifting off the tool compartment allows the fuel tank to be slipped from the rubber mounts and be removed as well.
Access to the battery and various electrical components is complicated, a factor that will probably lead to their neglect and eventual failure. The battery is so well hidden down inside the plastic shrouding behind the engine, one wonders how anyone installed it to begin with.
Framework on the Pioneer was always a careful blending of Ossa Stiletto characteristics with enduro and trail riding needs thrown in. Now the SDR supposedly combines woodsy traits of the Pioneer with the higher speed handling capabilities of the Stiletto racer which is almost the same, but better. We can say that the handling is as good as any Pioneer we’ve ever ridden, but better? No.
As before, the frame is made from mild steel tubing. Double downtubes run from the steering head and curl under the engine, to bend upward again and connect with the seat and rear tail framework. The heart of the unit is a 1-3/4-in. diameter single backbone tube that provides a solid mounting location for the rear of the engine. It bends upward from here to join at the steering head. Ample gussets are found at all stress locations, and 1-in. diameter tubing is used throughout, with the exception of the large backbone tube section.
The swinging arm is stout enough for the roughest use, incorporating an additional strengthening member in the form of a cross brace tube just in front of the tire. All welds show good penetration and a fair degree of workmanship. Even though frame materials could be of a higher quality, we have never heard of failures or problems in this area.
Akront polished alloy rims have always been noted for their strength and appearance, but suffer from the disadvantage of a deep lip in the rim surface. This has a tendency to collect a build-up of mud and debris, adding weight you don’t need. But this isn’t really too serious a problem, not at all like the one we’re about to harp on.
At the rear wheel, Ossa has fitted one of the largest tires we’ve ever seen on a 250cc enduro machine. The 4.50-18 Spanish made Pirelli gives excellent traction with its motocross tread pattern, but creates several problems at the same time. The swinging arm on the new Ossa simply was not designed to house a tire of such dimensions.
As a result, the rear tire and wheel cannot be properly aligned. Make the alignment perfect and the tire rubs heavily on the chain guard. Change it the other way and it rubs on the side stand when it’s in the folded up position. So the rider is left with a choice: either align the wheel so it doesn’t make contact with any of the machine, which is not aligning it at all, or purchase a smaller tire.
Not only does the tire rub on the side portions, but on the top as well. The tire on our test machine rubbed its way through the inner fender sections, and successfully ripped out the taillight wiring in just five minutes of riding. But this was only partly the fault of the tire. The rest of the blame must go to the springs fitted to the rear damper units.
Manufactured for Ossa by Betor, the springs are rated about 30 lb. less than what was specified by Ossa. Constant bottoming results. The problem is now in the process of being corrected, but that does not alter the fact that a large number of the SDRs reached these shores with totally inadaquate rear suspension, even though the damper units themselves are very similar to those fitted to Pioneers.
Front suspension was considerably better, but only after some fiddling with different viscosities of fork oils. Too, the Betor units had a penchant for leaking around the seals, but this could be cured by the owner with a little work.
One of CYCLE WORLD’S staffers took Ossa up on the claim of enduro capabilities for the new model and entered the annual High Mountain Enduro in California. Close to 100 miles in length, the High Mountain usually spares neither rider nor machine, and this time around was no exception.
To meet the street legal requirements of such an event, all an owner need do is fit a rear view mirror; the rest is provided by Ossa. The SDR is complete with legal head and taillights, necessary reflectors, an operational brake light with front or rear application, speedometer, and adequate muffling.
Our SDR started the event with less than 40 miles showing on the VDO odometer, and puffing smoke a bit heavier than normal due to a purposely rich fuel mixture. Still, it seemed perfectly content to fire after a couple of easy kicks. Just turn on both sets of petcocks, the ignition switch, and “tickle” the 32mm Amal carburetor until fuel dribbles from the bowl. The left side mounted kick lever is somewhat awkward to use, however, and further inconvenience comes from the lack of primary kick starting. This necessitates finding neutral before the rider can give the lever a shove, which can be quite a hassle on the side of a hill.
Spark arresters are a requirement at most events around the country, and always in California, which was a subject of concern for our rider at the High Mountain. Ossa has indeed fitted an arrester to its new exhaust system on the SDR, but has not gone through the necessary steps to have it approved. In reality, the machine is legal, but technically, a law breaker.
A Forest Ranger gave ours an okay, but things could get sticky without the official stamp of approval. Ossa should take the steps needed to make the unit officially legal.
Rider position on the Six Days should be close to ideal for most, whether sitting or standing. The seat might be too small for larger riders, but our staff testers were perfectly comfortable.
The new Ossa impresses one with its quiet; the quietest Ossa yet. And impressions are again made when the rider gets underway.
Like the Pioneer, low end torque is abundant. Point the SDR at any hill, and the combination of the torque and superb traction take the rider and machine to the top without fuss. The High Mountain had all sorts of climbing tests, and the Ossa passed them all. But right from the beginning, one problem was obvious—those rear shocks.
OSSA
250 SIX DAYS REPLICA
$1180
The units made it difficult, if not downright dangerous, to ride at a fast clip over rough ground. As a result, we had to be content with a fairly moderate pace for most of the event. With the progressive rate shock springs in the stiffest position and a 145-lb. rider aboard, bottoming was sometimes so severe that wheel lockup would occur when the tire lugs caught on the bolts that hold some of the fiberglass in place.
One of the enduro rider’s main complaints about the Pioneer was the lack of top end power. The SDR is supposed to put an end to those gripes, while maintaining the bottom end punch that was a Pioneer trademark, but it doesn’t. Ossa’s reliable piston-port two-stroke needs a few design changes.
The pressed together crankshaft still rides in two ball bearing main bearings, and most internal components are as before. The connecting rod big end carries a caged roller bearing while the small end uses a needle type. Piston rings are spring steel and quite flexible.
The aluminum cylinder barrel with pressed in liner is much the same as the one found on the old four-speed models, with subtle porting changes. A step backward, perhaps? Horsepower increase is said to be attributed to the 32mm Amal carburetor and the new exhaust pipe.
The Amal unit is a switch of sorts for Ossa, which usually fits its machines with IRZ carburetors. Yankee Motors, the Ossa distributor in the U.S., tells us that the IRZ people simply couldn’t supply them with enough units, so the switch to Amal was made. Look for Amals to be popping up on other Ossa models as well.
We noticed no particular change in performance with the Amal unit, and in fact, none of that increased horsepower, either. The 250 Six Days seemed to run about the same as Pioneers we’ve been on in the past. Our runs at the dragstrip confirmed our suspicions. The new Replica bike was actually marginally slower than the 1971 Pioneer we last tested. Top speeds were nearly identical, but acceleration times had dropped.
The infamous High Mountain Enduro pointed out a few more flaws with the Six Days. While it does provide the owner with all the needed electrical items for street legality, their operation leaves plenty to be desired. Less than halfway through the event, the only thing that still worked was the ignition switch. We had no lights of any kind, no horn, no nothing.
A winning enduro rider also depends on a fairly accurate odometer for his mileage checks. The VDO model fitted to the SDR will only give the rider a rough “guesstimate,” a serious flaw on an enduro bike.
Certainly no machine is perfect, but it only seems logical that a motorcycle designed for the ISDT should have a reliable electrical system, proper suspension components, and ease of accessibility for quick repairs.
There are some nice touches, however. The new 250 uses grease fittings on the cables and speedometer drive unit, and a leatherette boot to deflect water away from the air filter housing. Wire cables also are provided on the shift and brake pedal levers to deflect branches and debris that could foul their operation or snap them off completely. Another plus is a lightweight skid plate that is formed so that it keeps mud from being thrown into the cooling fins of the cylinder.
Ossa has the important basics down, and the Pioneer is an excellent example. It is just unfortunate that the SDR doesn’t handle any better, isn’t any faster, and is more expensive. Next | year’s version is supposed to offer much more with features like conical hubs and a chrome moly frame. Too bad they let this one get out in the meantime. It makes you wonder why they bothered....
