Power and Torque
Like I said, it’s not always about peak power and torque, it’s about how it’s applied and controlled. On paper the ZX-10R and despite having 200bhp+ next to its name, it still falls below its nearest competitors but when ridden back to back, those sort of figures would be barely noticeable. On the Bedford Autodrome’s SW layout, there’s the benefit of some longer sweeping corners, a couple of hard braking zones into sharper turns and then a mega, long, top-gear straight where 175mph can be achieved. Coming out of a slower second-gear left that opens gradually onto that back straight offers a chance to explore mechanical and tyre grip, chassis balance, suspension settings and the audio coming from the airbox gulping in huge breaths while the exhaust sang an appealingly raucous note. All while the throttle is pinned and the bike sits skilfully stable. It picks up from the lower revs noticeably better than the previous generation and then barrels quickly towards the 13,200rpm red line. Too quickly for me on a couple of occasions… #limiter. Any performer able to pump out a double tonne of horses is going to be invigorating but, as Pirelli said back in ’94, ‘power is nothing without control’ thankfully for all the throttle and tyre bullying I dished out, I could almost hear Kawasaki’s engineers egging me on to try harder.
I was going to make this point in the next section but for all the commendable engine revisions to comply with the latest set of emission regulations, and for all the power the 998cc four-cylinder has to offer, I couldn’t help feel its restrictions. Like a caged lion crying to be set free. And that’s where World Superbikes and British Superbikes step in to offer that release.
Engine, Gearbox and Exhaust
Manufacturers are really earning their dollars with Euro 5 compliance by maintaining (or sometimes enhancing) performance while still offering a cleaner engine. Kawasaki’s take on it has been to furnish the 998cc inline four cylinder-powered motor some new components. Namely a WSBK-derived air-cooled oil cooler, repositioning of a catalyser to heat up faster, shortening the first three gear ratios plus larger rear sprocket (up from 39T to 41T) for quicker acceleration. And however those small those amends sound, it’s made a vast difference in the way the engine spins up and offers much better performance in to and out of slower corners. In Sport mode the bike delivers its full power though I rode most of the day with the traction control on its lowest setting which still offered enough intervention to prevent the rear from sliding. The faster and more controllable acceleration will be an immense upgrade for any road-riding ZX-10R owner.
Gearbox-wise, the new ratios make a positive difference to make the bike much more rideable on the roads but also to drive out of those slower corners, although first gear will still take you beyond 90mph. With the digital rev counter flies toward the red zone at 14,000rpm, and you keep feeding the gears in with that superb quickshifter that clunks deliberately at 100% throttle yet is super smooth at lower rpm. Interestingly there didn’t appear to be a hard limiter in fifth and while I played with short-shifting in places, much like the V4’s of some rivals, the Kawasaki has plenty of torque to offer competitive pull when it’s easier to leave it in a higher gear. I did notice a small lurch forwards when rolling off mid-corner but barely worth writing about.
The standard-fit silencer might not be a beauty, but it sure does sound good. I’m not sure I’ve heard an inline four-cylinder growl as much, but Kawasaki have increased the length of it by 126mm and increased the volume as part of that emission clean-up operation.
Much like the latest derivative of the Honda Fireblade, the ZX-10R is a racing thoroughbred with many components shared with the RR version which will be competitive in the Superstock classes around the globe. That of course makes it at home on the track and while we didn’t get to ride on the roads, I’d certainly recognise the gearbox amends would make it more suitable than the previous generation.
Kawasaki Ninja ZX-10R (2021) Comfort and Economy
Ah, a section of the standard review template not necessarily designed for sportsbikes but with the handlebar and chassis adjustments in mind, I found my upper half with just the right amount of room in which to move around the bike and get tucked in as much my unfit 6ft/14st frame would allow. The higher pegs offer loads of ground clearance at lean and promote an athletic and aerodynamic position with which one can man-handling the bike. The gearshift is ideally placed and how’s this for attention to detail… Mr Rea asked for the rear brake reservoir to be moved so the rider could move their boot around more freely.
My only gripe about the comfort, and it was exaggerated when sitting on Rory Skinner’s FS-3 race bike on display in the pit garage, was the angle of the brake and clutch lever. Adjustable I’m sure but a little too high in its standard location for me.
I’ll glaze over the economy section on the basis this was a track-based test though the manufacturer claims a hefty return of 47mpg, so with a 17-litre tank that would, in theory return a barely believable range of 170-miles.
Handling, Suspension and Weight
Despite lacking the blatant winglets that many of its rivals have sprouted, there are aerodynamic surfaces hidden behind the fairings either side of the headlights, creating a claimed 17% more downforce than the previous design. What’s more, the nose reduces overall drag despite being less pointy than its predecessor, with a noticeably taller screen to let riders tuck in better. A welcome benefit.
Even the back of the bike, which looks much the same as before, is actually new. There are slots in the sides of the tail to let air through, further reducing drag, while the side panel changes improve aero efficiency and help guide engine heat away from the rider.
Looking at the bird-like beak, Kawasaki didn’t just offer a competition winner the chance to design the front end, this is the company that designed the Japanese Bullet train, they have one of the world’s best wind tunnels, and they have an engineering department dedicated to aerodynamics – they know how to make things go fast. And while competitors have blue-tacked some appendages onto existing fairings, Kawasaki have designed an entire ‘wing’ that is the front end of the bike that increases downforce yet has less drag than the old bike. Could I tell? Well, without the benefit of a back-to-back test what I can say is that the application of full throttle at corner exit didn’t promote any form of instability or indeed wheelie. Hard on the brakes and once again the Kawasaki kept calm and under control. With confidence building each lap, I’d push a little more with the front’s grip and then show a little more keenness to get on the throttle earlier and yet the bike was smooth in the transition with no head wobbling. It’s one of the most manageable sportsbikes I’ve ridden.
It’s not just the fairings that affect the aero of a bike. The lump controlling throttle inputs has a fair say too which is why the revised riding position is a blessing. Plenty of room to shove your bum back against the pillion seat and enough room under that screen which with its erectness almost looks like a TT machine’s.