All we've ever wanted is more horsepower and greater lean angles. Our desire led manufacturers down a path of producing tire-scorching production literbikes, MotoGP race replicas, and homologation-special superbikes—all of which are available to anyone with a willing checkbook. But what if we maybe got it just a little bit wrong?
Sure, mass horsepower and unlimited budgets are truly awesome, but it isn't everything when it comes to sportbikes, and the Kawasaki Ninja 400 and Yamaha YZF-R3 are proof. Performance is both exciting and educational. (Bear with me.) Relatively-low seat heights, user-friendly yet entertaining power, nimble handling, and affordable prices entice new motorcyclists. But even experienced riders will find these bikes challenging to ride fast, and their daily appeal is universal. Even better, this class of sportbike can help riders of any skill level master fundamentals and hone skills. Don't believe me? Our group of testers included licensed professional roadracers down to daily commuters, and the smiles never stopped.
So, while 1000cc sportbikes have their merits, we might consider lightweight supersports riders’ motorcycles. Meaning? There isn’t an excess of horsepower to fall back on if you don’t make a clean corner entry or quite hit the perfect line. Fast lap times come only if you make precise inputs, destroy apexes, and carry momentum. It makes small errors easy to see, while also making potential consequences less grave. The education this provides lasts a riding lifetime.
These class-leading small sportbikes are so capable that we first tested them at the racetrack, despite the bulk of buyers using them as streetbikes. And there is a bulk of buyers: The lightweight-supersport segment makes up nearly 40 percent of all supersport sales in the United States, a majority of those going to first-time riders. Impressive figures, representing serious growth potential for the entire onroad market.
The 2018 Kawasaki Ninja 400 is Cycle World's Ten Best Bikes Lightweight Streetbike winner and the performance benchmark for the small-displacement supersport segment. Following successful runs at 250cc and 300cc, Team Green upped the ante last year, bumping the parallel-twin's displacement to 399cc and heavily revising its tubular-steel chassis. The overhaul was a great success, helping carry on the lightweight Ninja's title of best on-road seller in the Kawasaki lineup, while offering riders more room to grow than previous iterations.
Yamaha responded in 2019, updating its YZF-R3 with visual and aerodynamic changes claimed to make it 7 percent more slippery and raise top speed by 5 mph—in a class of moderate horsepower, every last bit of speed helps. The R3's 321cc parallel-twin is unchanged, but the bike does receive a 37 mm inverted KYB fork—replacing a 41 mm conventional unit—LCD dash, and more aggressive ergonomics. Yamaha says more than 20,000 YZF-R3s have been sold in the past three years, accounting for nearly half of all R-model sales.
We know most riders use these bikes as transportation, but just look at them. Echoes of World Superbike and MotoGP reverberate off their bodywork, not to mention that both manufacturers feature track-riding shots on their respective websites. So we put the sporting qualities of the Ninja and R3 under the magnifying glass at Chuckwalla Valley Raceway in Southern California.
The 17-turn, 2.68-mile racetrack offers a mix of fast fourth-gear sweepers, medium-length straightways, hard acceleration zones, and dramatic elevation changes that add up to a perfect place to hammer these bikes. But before any wheels were turned, both competitors were weighed, measured, and run on the Cycle World dyno. We then spooned on Dunlop's excellent Sportmax Q3+ sport tires to ensure equal grip.
Analyzing dyno charts paints a clear picture of the Ninja 400's 78cc displacement advantage. The Kawasaki used its 399cc to belt out 43.4 hp at 9,900 rpm and 24.7 pound-feet of torque at 8,300 rpm.
Yamaha's YZF-R3, on the other hand, produced 36 hp at a higher 10,700 rpm, and 19.8 pound-feet of torque at, again, a higher 9,000 rpm.
Looking closely at the charts, it’s important to note that the R3’s torque curve is much flatter than that of the Kawasaki and power drops off more dramatically as you approach redline. The flat, smooth curve makes it tractable, but the top-end drop-off suggests that extracting speed from the Yamaha means riding in a small window of rpm range, and making precise shifts—working hard to keep it spinning near peak output. Meanwhile the Ninja’s torque curve is steeper in the midrange, and it pulls longer after peak output, giving useful overrev and more flexibility in shift points.
It’s no wonder then that the Kawasaki feels like a missile, consistently topping out as much as 8 mph quicker than the Yamaha on Chuckwalla’s main straight. Rolling on the Ninja’s throttle produces immediate power above 7,500 rpm, pulling stronger out of slow corners and walking away from the R3. The added low-end grunt makes recovering from mistakes easier on the Ninja, too quickly bringing you back up to speed with the turn of a throttle. Ask any of our testers, they’ll tell you that the Ninja’s 24 percent power advantage goes a long way in raising its racetrack fun factor, with most saying it has all the power needed to never let the entertainment wear off.
So, simply because its smaller displacement, gear selection and maintaining momentum is crucial on the R3—without revs near 9,000 rpm and the perfect line, the Yamaha is a sitting duck. Real-world torque performance matches the charts, meaning the Yamaha has to be ridden in the upper rev range to really keep it moving. In a sense, that the bike demands to carry corner speed is better for rider development, and the bike’s better chassis and braking feel also help it here. But racing a 321cc bike against a 400 makes for a frustrating speed differential on track.
The R3’s superb front-end feel makes up for lost ground at corner entry, even if a lack of a slipper clutch hinders its true potential. Without a perfectly smooth clutch release, downshifts are abrupt enough to upset the Yamaha’s chassis, forcing it to miss lines and kill momentum. Smooth is fast on the R3. Refine your downshift technique and the Yamaha will reward you with a confidence-inspiring feel from entry to exit. It’s nimble on its feet, enabling midcorner steering corrections when needed and tackling side-to-side transitions with more aggression than the Ninja. The Yamaha is a very sweet-handling motorcycle.
That’s not to say that the Ninja’s chassis isn’t capable, but it lacks the refinement and control of the R3. Even subtle inputs can cause chassis weave under braking, and suspension feel is numb by comparison. Also, aggressive brake application causes the fork to blow through its stroke and hit bottom. All this robs confidence needed to push braking limits. And its relatively low footpegs drag sooner than on the Yamaha, which is an annoyance after a couple of laps.
While the Ninja’s brake test numbers are better, at the track stopping power is comparable because you rarely brake at 100 percent. The Yamaha shines due to lever feel and because the stiffer fork rides higher in its stroke. Trail braking deep into Turn 16, the R3 lets you know exactly how much brake pressure is being applied, and how much there is left to rely on. The Ninja fails to provide the rider the same feel, though clearly it has excellent braking power. A swap to a new brake pad material would likely improve feedback on the Kawasaki.
Regardless of chassis shortcomings, the Kawasaki was favored on track simply because its fun factor was easier to access, even discounting the 4.2-second advantage it presents in lap time. The Ninja’s power, slipper clutch, and almost-as-good handling is an ideal platform for inexperienced riders in need of room to grow, but thrilling enough that professional racers exit the racetrack with a childish giggle—43 hp has never been so fun!
Around town, the Kawasaki continues to shine. Relaxed-forward-crouch ergonomics make for low wrist pressure, while a comfortable reach to the footpegs make the Ninja a great daily riding companion. The larger engine easily accelerates through traffic and maintains freeway speeds at lower rpm.
Its softer suspension—a nuisance at the track—is also preferred on the road, soaking up imperfections in the asphalt, not jarring off of them like the R3.
The YZF’s short first gear might make it easier for new riders to launch without stalling, but if your clutch technique is wired, the ratio is frustratingly short—requiring rapid shift to second accelerating from stops. Free thinkers might start in second, but that means extensive clutch slipping if you want to leave the line with any authority. A tall sixth gear and superior wind protection offer comfort at highway speeds, even if the R3’s powerplant lacks the oomph to confidently pass traffic even though it is spinning faster at equal speed. We loved the Yamaha’s aggressive ergonomics on the track, but it is less comfortable on the road than the Kawasaki.
Both competitors are priced at $5,299 with ABS, but present two very different characters. The Yamaha comes off as a lightweight racer. Its chassis is solid, yet nimble, and begs to be ridden with aggression, but its lower displacement holds it back versus the Kawasaki. Get two or more R3s on the track and you’d have a great race and an excellent learning experience. Could there be more displacement and an R4 in the future? Or is the counter-argument to displacement creep being the question of when to stop, because if you want more power why not go 500cc or even 600? Or 1,000?!
After our extensive seat time, we think creeping up to 400cc is just about right. The Kawasaki engine finds a real sweet spot for power, giving newer riders something easy to control while fast folks still have serious fun.
The Ninja chassis does have minor shortcomings at the track compared to the scalpel-like Yamaha, but the Kawasaki’s trade-off is more comfort on the street. And the chassis is a solid performer in the real world. Its balance of power is truly excellent. We cast our vote for a sporting, affordable 400 from every manufacturer, and not 1cc over, please.
