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Moto Cross comparison test (250 cm³]

Silver Arrow Company

Silver arrow with a difference. The new quarter-liter crosser from Honda with an aluminum frame sets new standards in motocross sport. The competition is already out of date?

Racing drivers don’t like their fellow men. Just like when the big party in the paddock always ends in an argument every weekend? In the dispute over the best lap time, the best starting position or the place on the podium.
But Honda has found a means to unite the self-loving bunch at least for a moment: the new CR 250. Special feature: bridge frame made of aluminum profiles. The absolute novelty in off-road sport. The shimmering silver decoy for collective desire. Or quite simply: the bike for sport – alone against everyone.
Just with its aluminum frame, its Keihin carburetor with electronically controlled accelerator pump and its DRA, an ignition adjustment, which in practice sets the ignition point extremely late when the engine speed increases too quickly and thus wants to operate as the first traction control in the Moto Cross profession.
But too many new things are often unhealthy, hopes the competition, despite the generally youthful, poppy outfits against the Silver Arrow, comparatively staid-looking competition. And maybe she’s right. After all, the remaining oven candidates in the comparison test – Kawasaki, KTM, Suzuki and Yamaha – can at least offer what has been customary and good in off-road racing up to now. Single-cylinder two-stroke engines with exhaust control systems, which noticeably educated the poisonous racers to continuously deliver power across the entire rev range, and handy chassis. But wait, at least Kawasaki has been using the bridge frame since 1990. Made of steel, of course, but still.
Enough of the preface, what matters is what comes out at the end. Seat rehearsal. Respect, the bench nose of the CR is very flat. If you want to slide far forward in the corners for better weight distribution, you can let off steam. Otherwise, the team feels different despite everything. Honda – the narrowest of them all. Just 16 centimeters wide at the knee, despite the bridge frame. Suzuki – slim and stocky, almost like the Honda. Yamaha – a bit bigger, but still an ideal figure. Kawasaki – stomach is okay, but a bit thick around the sweeping radiator wings. KTM – light bacon belt around the tank, everything seems bulky. Europeans instead of Japanese.
What’s that supposed to be sitting around? Drive please. And that no one is put in the wrong corner, five sets of Dunlop D755 have to leave their cleats. Made as a sacrifice to please the gods of the furrowed, plowed and stony cross-pistes in northern Spain. The drivers, of course, not the material. Because that is supposed to prove what is going on under these circumstances.
But pretty one after the other. In order to avoid confusion, the first thing to do is to classify. Sitting position – already checked. It continues with the engine, fork, shock absorber, driving characteristics and brakes – always all against the Honda.
So point one: engine. Let’s start from the back. The Yamaha always only wants one thing – to please the amateurs. The YZ pushes like a small tractor. Full feed from the tightest bend, manageable power to mid-speed, which then flattens out at the top. Good for normal crossers who struggle on bumpy ground with more essentials than the finely dosed play on the clutch lever. But bad for experts who like to save a gear change with high-revving motors. To the Suzuki. Even if the yellow one took possession of the Honda technology at that time before a year, Mendel’s laws of inheritance cannot be completely overridden. In other words: passable at the bottom, robust in the middle and no end at the top – Suzuki have always felt most comfortable at high engine speeds. Now, however, with significantly more bite in the mostly used medium speed range.
Only the KTM celebrates even more than the Suzuki. In the speed cellar, clearly the most timid of the bunch, she bites mercilessly at mid-speed and doesn’t let go up to the top. Nothing for supercross but a hit for open-air slopes.
Break. Still pause. And it is precisely with this gap that the leading green-red coalition dominates, at least in the engine classification. Kawasaki: Performance where it is needed. Below, middle, above – the green one is always ready. Whether on the washboard, in front of table tops or just on the long straight start, the KX is bursting with enthusiasm. Just like the Honda and yet completely different. The CR too has a lot of fire. Also below, in the middle and above. But the silver disc provides gentle pressure. As if a rubber band were woven into the throttle cable, the CR only builds up as much speed as the rear grinder can bring to the ground. But this from idling to the very highest speeds. A dream for outdoor cross of all variations. However, some supercrossers were already using their livelier 1996 engines in the past indoor season. But strangely enough, the Honda aluminum frame already leaves its mark on the engine rating. The vibrations of the Honda unit are clearly noticeable transmitted from the massive chassis to the handlebars.
Next chapter. Chassis, paragraph fork. It is a pity that the manufacturers can only gradually part with the poorly appealing and dirt-sensitive upside-down forks. Only KTM and Suzuki have so far left the wrong technical path and are making the Crosser existence worth living again with the return to the fork technical origin.
Whether it’s the brand new Magnum fork from Marzocchi in the KTM or the elaborately constructed Showa in the Suzuki, the traditionalists degrade the rest of the field to air pumps in terms of responsiveness and puncture resistance. The only flaw: the spring rate of the Marzocchi fork was clearly too soft. Fast and heavy pilots are not the only one is who cannot avoid switching to harder springs. But then everything fits.
And there we have our distance again. This time down to the green-red-blue upside-down league. Because even the KX fork, as it were a one-eyed among the blind, can only shine with acceptable response behavior, but with its soft tuning it slams mercilessly on the block with every hard landing. The fork of the Yamaha works a lot worse. The Kayaba part clearly hits the handlebar grips in the palms of the hands, especially on the dreaded sharp-edged bumps. And the Honda? This shows in this regard in the bad old tradition. Almost according to the motto, a good ending adorns everything, the Showa fork in front of the noble aluminum chassis shines with a soft end stop, but it is reluctant to be moved to work by smaller shafts. Conclusion: Without expertly revised coordination, the horror of all Crossers – the dreaded cramped forearm muscles – will remain a constant companion of the Kawasaki, Yamaha and Honda followers.
Still chapter chassis, paragraph shock absorbers. The world is moving a little closer together – and revolving around Austria or Sweden. With its enormous adjustment range and legendary quality, the Ohlins shock absorber from KTM sets the bar in the crosser profession. It has to be like that. Kayaba also has the set-up of her shock absorber in the Kawasaki under control. Fine comfort and rich traction make the KX hindquarters the best-sprung rear of all Japanese.
And that distance again. This time blue, yellow and red can be suspended. Whereby the Suzuki pulls out of the affair best, even if the hindquarters are still too hard even for fast-paced contemporaries. Butt up, is the driving style tip with the equally uncomfortable Yamaha, and the Honda can be glad that the silky engine whitewashed the weaknesses of the shock absorber on acceleration edges as well as it can. The US importer reacted promptly and had everyone destined for America VS.Deliver the R 250 with revised damper elements.
But now it’s getting tight. And there the Honda can shine as outrageously as its frame. Because there is nothing that whistles around tight corners faster, more precisely and more controllably than the Honda. All the more astonishing as the aluminum Honda hardly has to pay tribute to its straight-line stability. She fidgets, but hardly more than the rest of the generally nervous Crosser guild.
Only the Kawasaki pulls its tracks with comparatively stoic calm. Not only hobby crossers like to pay for the gentle treatment of nerves and fitness with a little indolence in the curves. The longer the race, the more the limp body and mind will appreciate the gentleness of the KX.
The Yamaha also shows its handlebars relative grace. All the more astonishing, as the YZ also knows how to combine the relative stability on straights with a remarkably secure bite of the front wheel in tight corners. Suzuki and KTM decide more clearly. The RM likes it in the narrow run and shakes the front part negatively on bumpy straights. The SX, on the other hand, is happy when it can finally let it run on the straight again after an uncomfortable circle of corners.
And last but not least, the chapter on brakes. All five savages are almost entirely at a high level with the Honda stoppers as reference models. Shortly afterwards Kawa, Suzuki and Yamaha. Only the KTM is a mess. Tea forehead has to be pulled harder than the competition, and at the rear the Brembo calipers tend to lock the rear wheel.
So, it’s time to end the battle of technologies. But if you fight everyone alone, you have little chance of victory. The new technology from Honda clearly sets the tone for the future of off-road sports. However, in order not to let high-tech become an end in itself, a coordinated overall concept is required. And this was indeed tinkered around a bridge frame in 1997 – but around that of the Kawasaki.

1st place – Kawasaki

Instead of spectacular innovations, Kawasaki relied on optimizing the existing. With success. The interaction of the engine, rear suspension and stable chassis brings a lot of confidence. So much that even the far less optimal front fork can be accepted.

2nd place – Suzuki

The little yellow one knows that especially in racing many average results can lead to a good overall result. This is why the RM doesn’t let itself go far behind and, in the end, overtakes most of its competitors with its excellent fork and impressive agility.

3rd place – Honda

The technology of the exciting Silver Arrow clearly sets the standard in motocross. But despite the fantastic engine with trend-setting innovations, Honda has remained true to one tradition of all things. Namely, braking a perfect motorcycle with unsuitable suspension settings.

4th place – KTM

Years of hardship have borne fruit. The 1997 quarter-liter model from KTM has caught up with the standards of the Japanese crosser. The advantages of the great suspension and the powerful engine far outweigh the disadvantages of the mediocre brakes and the unusual ergonomics.

5th place – Yamaha

Actually, the YZ could have copied the Suzuki’s recipe for success. However, the Yamaha can only compensate for many average results with a single highlight, namely the very pleasant to drive engine. But that is precisely what is no longer enough for a place in the sun in the closely spaced quarter-liter field.

Torsional stiffness – measurement instead of feeling

Does a Moto Cross frame have to be as resistant to torsion or bending as possible, or should it be more flexible? This question is controversial among drivers and experts alike. In the past, the frames of the Crosser were like an egg to the other: central top and front tube, beams in front of the engine up to the strut mounts divided. The two-dimensional control head area could not do much to counter torsional forces. That changed only in 1990, when Kawasaki presented a new concept with the perimeter box frame with a double loop, rectangular tubes and spatial stiffening of the control head. In the road sector, very stiff frames with wide profiles between the steering head and the swing arm bearing have long been widely accepted, and Honda has taken this concept up with the new CR 250. The Japanese propagate significant weight advantages with greater rigidity. MOTORRAD wanted to know more: The cross machines were stripped, weighed and put on the test bench at the University of Zwickau under the direction of Prof. Dr. Peter Gartner checked for their actual torsional rigidity. The result is surprising. As promised, the Honda frame is lighter than the steel competition – the difference is 600 or 800 grams – but when it comes to rigidity, the aluminum part has to be clearly guided by the relatively broad Kawasaki chassis. As expected, Yamaha followed by a large margin as the representative of the group of single-loop frames. Surprisingly, the difference in the torsional stiffness of the rear wheel swing arm is almost the opposite. Yamaha brings it with strong profiles to 1197 Nm / degree, the visibly more delicate Honda swingarm only to 522 Nm / degree. At 746 Nm / degree, Kawa is in between. GT

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