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Test: Yamaha WR 250 F

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Young and wild ?? Yamaha tries the rebellion with 250 cm3. Real alternative or kids’ stuff?

"Hey, the kids‘track is over there. "Simply wonderful, this reception in the paddock, here the engine-size machos are still among themselves." A four-stroke engine with 250 cubic meters, that can’t be anything. "Somehow the little Yamaha must have noticed something, in any case she tries to hiss very, very badly from her stainless steel pot when warming up between the large-volume colleagues. But it doesn’t work. Okay, at least you don’t attract attention with the whisper, you should see things positively.
With the brand new WR 250 F, Yamaha is the first manufacturer to offer a real competition enduro for the four-stroke class up to 250 cm3. And in doing so, an existing engine was not simply reduced in displacement, but a new, ultra-modern power pack was created. With a stroke of just 53.6 millimeters and a cylinder diameter of 77 millimeters, the water-cooled single is designed with a very short stroke. Supported by a balance shaft, which keeps the inertia forces in check, speeds of up to 12,500 rpm are possible, then the limit intervenes. The gas exchange is handled by five ultra-light titanium valves, which control two overhead camshafts with fixed-speed bucket tappets. These key data may appear extreme for enduro conditions, but sporty four-cylinder engines with comparable individual cubic capacities can handle them without any problems. Mixture preparation is done by a Keihin flat slide carburetor with an accelerator pump, and a slide sensor informs the map ignition about the load status.
Knowing about the technical features strengthens self-confidence, so get out on the slopes. You begin to adapt your driving style to the WR 250 F during the first trial laps. The motto is: accelerate early, very early. And then the cable as quickly as possible to the stop. Practically at the same moment that the front wheel is on the intended course, you just snap open. Do not worry, the rear wheel does not suddenly break away as it does with many engine-capacity specimens, because the little one pushes very gently with a maximum of 23 Newton meters. So the blue pulls smoothly through the enormously wide usable speed range. Hectic gear changes? Not necessary, even at a brisk pace, the second and third gear stages of the five-speed transmission, which is much wider than the Cross sister, are sufficient on most routes. Tea offset built-in exhaust camshaft, the exhaust, the jets and the CDI unit also separate the WR from the YZ.
In the meantime, word has got around in the enduro camp that less power is often more. But that so little ?? that is 34 hp at 11200 rpm in the unthrottled sport version? completely sufficient for fast lap times, amazed. Because the WR 250 F is anything but slow. Because of children’s moped and such. On wet meadows or slippery clay soil? typical for many special stages ?? one pulls loosely in the notches past many a steam hammer, whose matador tries to walk the tightrope between slip and traction with a cramped gas hand.
The WR-typical soft suspension makes a big contribution to the enormous traction capacity. The fork and strut guide the wheels safely over narrow, muddled stretches of medium speed. For fast, wavy sections or for training on the cross piste, however, the pressure level should be a little tighter. Here one would like more reserves. The standard Michelin Enduro Competition III is also a perfect match for the enduro-friendly design. With their soft structure, they offer a secure grip on wet floors.
When designing the chassis geometry, the WR is based on the standard of the blue Crosser. The misshapen tank criticized on earlier WR models is a thing of the past. In Europe, all WR models are delivered with the eight-liter fuel bottle. All in all, it weighs just 114 kilograms (ready to drive without fuel). In the eleven extra kilos compared to the YZ 250 F, the lighting system, the ten percent larger radiator with expansion tank and the side stand, which is completely unsuitable for off-road use, are hidden – it protrudes far too far. Oh yes, a mechanical speedometer with horn, two mirrors and a steering lock are also on board.
W.he technical key data and the minimum equipment reveal it, the WR 250 F is a thoroughbred competitive athlete and has the road approval required for off-road sport. Its calling is uncompromising off-road use, where it is a real alternative to the established 400s. It cannot and does not want to be an everyday enduro à la DR 350. Sports drivers don’t mind that only 29 hp are legal on the road? it is throttled by a stop screw in the carburetor. And the short maintenance intervals are common in sports camps, whereby experience with the WR 400 F shows that, despite the complex technology, you rarely have to do a routine oil change.

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