Presentation of the Harley-Davidson XR 1200

Presentation of the Harley-Davidson XR 1200

Let’s get sporty

Success in racing is often sought. Especially when fame and splendor can shine on civilian life. In the Japanese camp, as with the Italian faction, it goes without saying that victories on asphalt are intended to boost business. In Austria and Bavaria, the Paris-Dakar material battles were used for many years to show the superiority of their own products. But why Harley-Davidson has not marketed the most consistent series winner of all time, the Dirt-Track-Queen XR 750 (see Dirt-Track-Story, page 52) at least for image purposes, is somewhat astonishing.

Her sports hit brings a lot with her that could also be useful in the European way of driving. Compact dimensions, for example, low weight and an opulent torque curve? all properties that are just as important in the slippery oval as on the Black Forest High Road. And properties that the prototype presented at the Intermot trade fair in Cologne XHopefully the R 1200 has taken over from its role model. Of course not one to one, a Harley sports replica is no better off than its counterparts. But in large parts.

In terms of performance, even in very large areas. The 750 series mobilizes between 90 and 100 hp, and Harley-Davidson advises 85 to 90 hp for its civilian sister. The XR 1200 would not only be the most powerful air-cooled Milwaukee twin of all time (which has been in service for a long time in a similar configuration in a Buell XB12), but would also be pretty much in the window that experts consider ideal for the highway becomes. Especially since a 1200 cubic hum for this output does not have to cheer in the highest tones, but delivers full thrust from the lower speed.

However, "Wuchtbrumme" should also describe the other, rather sedate side of the XR fairly precisely. At least if you apply international standards. In view of the mighty engine dimensions, nobody can count on the chassis data of a children’s bike or at least the dirt track model, just like the weight of an oval racer. In this respect, the XR 1200 should remain completely American despite all efforts (Dunlop qualifier tires in special 18-inch format, 43-series Showa upside-down fork, Nissin double disc system with four-piston calipers). But a pretty sporty one.

Drift elite in America – oval traffic

When America’s drifting elite meet, it gets hot and dirty. Then the cracks get it on ovals made of pure clay. And Harley’s XR 750 has been winning for decades.

Springfield ?? somewhere in Illinois.
Prairie right, prairie left, Lake Michigan to the north, Ohio River to the south. The Midwest in its typical form begins here. A city couldn’t be more American? and the sport that makes Springfield the "Capital of Dirt Track" is not American either.
Dirt track ?? or a more accurate flat track, because the lack of hills makes the difference to the equally popular motocross ?? You can theoretically operate it on any cow pasture if someone has removed the flatbreads beforehand. But even the Springfield cowboys don’t go that far. Instead, "Black Gumbo", the black clay, is dredged from the nearby Sangamon River and rolled into a mile oval. Compressed in this way, the silt turns into an amazingly non-slip surface. The best according to local officials. And just good enough for the "Springfield Mile".
The US championship was fought here until 1954. In a single race. Whoever won Springfield got the Grand National title including the coveted number 1 panel. Goal
those days are over. Just like that
The following epoch (1954 to 1986), when only one champion was chosen in 18 races across all asphalt and off-road disciplines. Probably also because a dirt tracker was regularly in front, because
the majority of the runs took place on loose ground. Today she writes
American Motorcyclist Association (AMA) held six championships, with the drifting artists even driving in two classes. The single-cylinder class starts on short tracks (400-meter oval) and in the Tourist Trophy (courses with right and left turns and a jump), the Big Twins on half-mile or mile ovals.
Which inevitably leads to Harley‘s XR 750. As unbelievable as that may sound, since it was first published
In 1970 the XR-Twin, based on the Sportster engine, is the measure of dirt-track things and thus marks a technological standstill that is unparalleled in motorsport. Only once, namely in 1972, was the XR 750 facelift and given a motor housing and cylinders made of aluminum alloy. The frames (monoshock frames have been established for about five years), on the other hand, have been the sole responsibility of the teams for a few years and have been further developed accordingly.
In view of these peculiarities, the dirt-track rookie also knows that here, on the watered and rolled sand or clay soils, different laws apply than are common in the motor sport world. It is not sheer power that makes the difference between victory and defeat, but one thing above all, despite top speeds of over 200 km / h and wild drifts in the corners: the easily controllable traction. With a sensitive throttle hand and a lot of momentum up the straight, make yourself small for a moment, then dive with a lot of momentum into the long, long left and again determine the lean and drift angle with the throttle hand? Rearwheelsteering is the secret of Dirt Track and one of the recipes for success with which the wild US boys Roberts, Lawson, Schwantz or currently world champion Nicky Hayden mixed up the motorcycle world championship. King Kenny started with the most idiosyncratic creation that the dirt track has ever seen: with the four-cylinder two-stroke Yamaha TZ 700, which connoisseurs attested to the power of a hand grenade. Roberts won a race only to say afterwards, "Yamaha isn’t paying me enough to ride again."
It is therefore not so astonishing that the non-American competition from Aprilia to Suzuki is approaching the top dog by backward tuning. The regulations allow 1000 series engines, 750 series racing engines and air-cooled 1250 series with pushrod valve trains. Suzuki, for example, has been gaining a foothold for years. First with the TL engines, currently with those of the SV. “We’re getting more and more competitive,” says Suzuki team manager Dave Burks. And that’s because they cut power in order to find traction. "This year we took out another eight hp." This means that the Suzuki twins have 86 hp, while the factory Harleys have between 90 and 100 hp.
In the races on the mile ovals, mind you, like here in Springfield (twice a year) and once in Syracuse / New York. In the shorter half-mile races, a different crankshaft with a 315 degree crank pin offset is used, which provides more torque
and provides less peak performance. Thesis
Version with the one single no
dissimilar performance characteristics is called "Twingle".
Why pulling through the dirt track plays a bigger role than pure top performance becomes clear when you look at the chronology of a "heat". After engaging the clutch at the start, the drivers step into speed level two as quickly as possible. Turn one (i.e. the first of the two oval curves) is fully accelerated in the third, before the fourth gear follows on the back straight. The fourth stays in until the end of the race, the engine speed is between 6000 and 9500 rpm. The gear lever is on the
right side above the brake lever for the rear wheel, there is no brake at the front.
And that’s a good thing, given the action on offer. In the first two-cylinder match of the season in Springfield, a top ten group drifted electrifyingly, wheel to wheel and arm to arm. There were half a dozen falls, two breaks in the race, and about 25 changes in leadership. In the end, reigning champion Chris Carr won ?? of course on the XR 750.

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