R7 2021
#51

Não sou especialista no assunto mas se calhar podemos olhar para as voltas mais rápidas das pistas para perceber se a potência influencia ou não a coisa. Pelo que estou a ler aqui, os recordes devem ser todos da Moto3.
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#52

(05-12-2020 às 11:19)pedromt07 Escreveu:  R3...Ninja400.

Gosto de qualquer uma delas.

Partilho uma review do ano passado. Artigo extenso mas vale a pena ler.

Citar:2019 Yamaha YZF-R3 vs. Kawasaki Ninja 400

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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!

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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.

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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?!

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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.

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Fonte: Cycleworld

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#53

Sempre houve "desportivas" de baixa cilindrada. Uma TZR ou uma NSR há 25 anos atrás eram exemplos. Era o mais parecido que um puto que se iniciava nas lides poderia ter em relação às motos das pistas (e alguns destes modelos até tinham efectivamente troféus mono-modelo).

Depois havia outras desportivas de baixa cilindrada (que já não estavam ao alcance de qualquer um), como as CBR250RR, ZXR250 ou GSXR250, com motores desportivos de 4 cilindros e multiválvulas, que eram praticamente cópias das irmãs grandes, em mecânica ou ciclística mas com motores de menor cilindrada, e com prestações que se evidenciavam. Segmento que tinha a mesma repercussão na categoria das 400.

Esta segmentação não é alheia ao reflexo que tem nos respectivos campeonatos do mundo de produção, como sejam as WSSP300 e WSSP600. As actuais 300/400 desportivas existem também por isso.

Agora... «desportivas destinadas a circuitos técnicos» é um segmento que nunca ouvi falar!

Uma R7 (independentemente de colidir ou não com a designação de outra moto criada em tempos para outros fins), com o motor de uma MT-07, não é nada de escandaloso e muito menos de novo. A Kawasaki tem há muito uma alegada "desportiva" exactamente com a mesma receita (buscar a motorização de uma utilitária), e não choca ninguém. Chama-se de Ninja 650 (e possivelmente esta sim, será uma concorrente directa de uma futura e hipotética R7 motorizada pelo CP2).

Agora, não venham é dizer que uma nova R7, com estes pressupostos, virá substituir uma R6 e muito menos, que será "aliciante" como tal... seja pelas specs da mesma, como por todo o historial e representatividade que a a R6 teve e tem no actual WSSP600, que quer se queira, quer não, é a montra das capacidades de cada supersport de produção, de cada construtor. Aliás, o facto de a Yamaha descatalogar a R6 mas mantê-la como mota de produção destinada às pistas, não é alheio a este facto... é que por lá continuam a andar juntamente a elas, as ZX6-R, CBR600RR ou as F3 675 (sendo que apenas esta última tem a sua variante de produção street-legal).

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#54

(05-12-2020 às 13:27)gonzas Escreveu:  Não sou especialista no assunto mas se calhar podemos olhar para as voltas mais rápidas das pistas para perceber se a potência influencia ou não a coisa. Pelo que estou a ler aqui, os recordes devem ser todos da Moto3.

Talvez o MotoGP com pilotos profissionais não seja o melhor exemplo. O melhor exemplo é a quantidade de pessoas com motas de muitos CVs que depois não andam um caralho, que beneficiavam mais de um motor mais dócil, um conjunto mais leve, ágil e fácil de conduzir.

Ditadura dos Flocos de Neve
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#55

A "mística" em torno da R7 dos anos 90 parece-me um bocado exagerada. lol

Compreendo que para muita gente possa parecer que a Yamaha fez algo "fora da bolha".
Mas na prática adoptaram uma receita que não era original.
E que no presente muitos continuam a recorrer.

Ou seja, lança-se uma moto parecida à versão "civil"...
Mas com specs adequadas a competição. E produzida num número suficiente para obtenção da respectiva homologação.

(Por exemplo exemplo a ZX10RR para 2021 segue esta abordagem)

Claro que não não vamos por isto desprezar a "velhinha" R7.
Era uma moto consideravelmente exótica para a época. Sobretudo para o que os japoneses produzam nessa altura.

Mas sejamos realistas... ninguém vai dizer "epah... a R7 era um canhão do meu tempo"!
Dificilmente alguém viu uma a circular. E dificilmente a irá ver.
Não foi concebida para isso. Foi concebida para fins desportivos e nem aí teve o sucesso da R45 cuja receita era a mesma.


Não me choca absolutamente nada uma R7 com a motorização da MT-07.
Muito menos chocaria uma R9 baseada na motorização da MT-09.

Obviamente que nunca serão verdadeiras supersport.
Até por razões de homologação.
O que não quer dizer que não seja opções interessantes e perfeitamente válidas para o mundo real.


Pessoalmente acho que o CP2 está no "sweet spot".
É um motor suficientemente dócil e intuitivo para quem tem pouca experiência.
Ao mesmo tempo energético e divertido o suficiente para condutores habituados a maiores potências não se fartem rápido.

O mesmo se aplica ao CP3, que se pode considerar perfeitamente comparável em diversos aspectos ao 765cc que actualmente fornece as moto2 do GP.

Agora... a derradeira questão é se estamos a falar das mesmas MT's com avanços ao invés de guiador e um kit de plásticos.

Ou se seriam dignas de receber algumas vitaminas no que diz respeito a suspensões.

Já nem vou falar de outros componentes como o quadro.
Porque acredito que iriam afectar substancialmente o preço, nomeadamente numa R7.
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#56

O futuro está nos 99, não está nos 299 smile
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#57

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#58

Está a parecer-me que algumas ideias da KTM percolaram até ao Japão.

Cilindradas moderadas, muitas cores jovens e divertidas, uma imagem fun.

Perde-se 40% da potência máxima e 50% dos cilindros? Não faz mal, apesar disso esta deve ser mais divertida.

PS: espero não ter ofendido ninguém.
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#59

pode ser uma trampa de motor mas de aspecto, esta lá! ok
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#60

Parece uma desportiva genérica de há 10-15 anos atrás. Gosto mais da R6.

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