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Comparison test KTM 250 EXC Racing / Yamaha WR 250 F

Filming

Open up, take off the film: the main actors have to prove what they can do in front of the camera. Is it just applause from the scene, or is it enough for a standing ovation at the end?

The smallest ones often spit the thickest notes. As if they were trying with all their might to attract Warning. The small oven-stroke machines from KTM and Yamaha are not interested in the spectacle, they just can’t help it. Their fate is life at the limit, because only at the highest revs can usable power be extracted from the quarter-liter displacement. While the confident, easy trot is sufficient for the large-volume machines, every single horse in this cubic capacity category has to transition into a straight canter.
There is a considerable amount of horsepower, because technically the small four-stroke engines have been upgraded enormously, especially in the last year. The time of the dusty, air-cooled oldies – often disparaged as air pumps in technical jargon – is over since Yamaha created the YZ / WR 250 F models a year ago, a true-to-scale reduction of the successful 400/426. From a distance, the 250s turn out to be largely identical on closer inspection: Everything is smaller, lighter, from the engine to the frame. KTM is taking a different approach with the new 250 EXC. The engine is an offshoot of the successful 400/520 models, most of the components, for example the engine block, are the same. In the case of the chassis, the only difference is the coordination of the spring elements.
The paper form speaks clearly in favor of the KTM: It is perfectly equipped for sports use, well thought out in a practical way, and the icing on the cake is the e-starter, which is rightly praised. The EXC has earned the nickname Racing, only the start numbers are missing. The road conversion kit is included anyway, but unfortunately the approval is only possible with strong throttling. The Yamaha can be legally moved with 29 hp. Physical effort is required when kicking off. This usually works at the first kick, only after a slip in the field, a few kicks are sometimes necessary. Service work is more cumbersome on the Yamaha, in this regard the KTM is exemplary.
But now to the all-important question: Can the Austrians with the downscaled ohc engine keep up with the more complex dohc Japan engine in terms of performance? According to the test bench diagram, it doesn’t look too bad at all, the KTM pulls itself up around the bottom, three horsepower is missing at the top. The EXC only struggles with the speeds, at around 10500 rpm it suddenly runs out of breath. Since the WR continues to blow cheerfully, it can easily be cheered up to over 13000 / min. Only at 13500 rpm does the limiter put an abrupt end to the drive.
If you turn the briskly whisk, you will keep the WR in the range of around 8,000 to over 13,000 revolutions, then at least 25 horsepower are always waiting to be used. Considering the displacement, a respectable range of a good 5000 rpm. To achieve a similar level of performance with the KTM, it would have to be moved between 7500 and 10500 rpm. So a belt of 3000 revolutions with less peak performance. It is astonishing that the Yamaha can manage the performance curve with the clogged exhaust, while the KTM is clearly audible – but by no means unpleasant – from its sports exhaust.
However, test bench diagrams are gray theory, especially for sports machines, and these two 250s are a good example of this. In real life there are phenomena that the measurement record does not show. With the Yamaha, the power builds up absolutely spontaneously and directly even in the lowest speed range; every throttle is converted directly into power at every speed. This is not mentioned in the diagram determined under full load with slow speed build-up. Certainly the little WR doesn’t have the thud of a 400. But when maneuvers are unsuccessful, brave progress is made even if the gear step and engine speed are completely out of the desired rhythm. The EXC likes to take a break in such situations and only gets going after a few seconds of thought. Obviously, the gas oscillations must first build up in the intake paths. This can be extremely annoying in practice. Especially when you don’t go full speed, but stalk through the woods on a trial basis. The EXC calls for a highly sensitive use of the throttle. This behavior is less of a problem for the enduro pro, who can keep the KTM on the special stage in the narrow band where it feels comfortable. The hobby enduro rider finds it much more difficult. Whoever wants to and can circle through difficult rocky passages with almost 10,000 revolutions?
It’s actually a shame, because the KTM’s chassis are absolutely top-notch. The coordination of the spring elements is sporty and tight with good progression, even high jumps on the cross piste or a table that is too short for the Austrian to digest without complaint. In contrast to this, the Yamaha is more of a softie, it can hit the front and back when driving hard. It also sways more over waves and holes; in comparison, the KTM is much more precise. One point of criticism of the EXC: When braking, it behaves a bit fluttery from time to time, strong gripping on the handlebars is recommended.
On the other hand, the soft interpretation of the WR also has positive sides. It is more comfortable and does not pass edges and holes so unfiltered on to the seated driver. And it is easier to steer and less straight up when you accelerate. Which certainly has to do with the sitting position. The Yamaha integrates the driver more, while the KTM tends to sit on top of it. Big riders tend to feel better on the KTM, while smaller ones prefer the Yamaha.
F.Yamaha’s performance is definitely enough for an Osacar presentation. There is a little bit of fine-tuning that could be done relatively quickly with tighter springs and a few modifications – and an electric starter. With the KTM, there are more substantial defects? they can only be outplayed with a great deal of commitment.

Conclusion: KTM 250 EXC Racing – 2nd place

The small EXC has to live with the compromise: The fact that it inherits many components from the larger models ultimately costs maneuverability and power and results in a delicate throttle response in the lower speed range. It’s a shame, because the chassis is sporty, the equipment high-quality and practical, the electric starter a stunner.

Conclusion: Yamaha WR 250 F – 1st place

The effort is rewarded: Yamaha has designed a fantastic 250cc engine with a wide range of performance, outstanding top performance and spontaneous liveliness. Only one wish remains unfulfilled: an electric starter. The suspension is suitable for soft off-road excursions, athletes need more hardness and progression.

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