BIMOTA KB4 (2022 - on) Review

Bimota’s KB4 impressed us on the road when we tested it in the hills around the Rimini factory back in June. The combination of light weight, high-spec and the flexible, easy-going Kawasaki Ninja 1000SX engine made for a bike surprisingly friendly and usable on the road, unlike the more extreme, race-bred machinery the company is best known for. But it’s no softy: the old chassis-building know-how still shines through on a track.

We rode the bike at the Autodromo di Modena, which is broadly tight and technical, with only one straight briefly letting you select fifth-gear. On paper, it’s better suited to a premium middleweight naked, or even something like a KTM RC390 (which was launched on this very circuit). But the KB4 acquitted itself far better than a litre bike should.

No, it’s not a hardened track animal. If you do all or most of your riding on track, the BMW M1000RR or various Ducati Panigale V4s available around the £30k asking price will be a better bet.

But for predominantly road use and maybe the odd road bike-only trackday, the Bimota KB4 is a strong alternative with performance to satisfy all but highly-skilled trackdayers.

Light weight is a key factor in the KB4’s track performance – it’s just 2kg more than the final model of Kawasaki ZX-6R weighed, some 40kg lighter than the touring-biased Ninja 1000SX it’s based upon. It does cost twice as much as the SX, but at least you can see where the improvement effort has gone.

It’s also very short, thanks to an underseat radiator fed by those distinctive air ducts running from the nose, through the fairing and into the self-supporting carbon seat. The design allows the engine to sit closer to the front wheel.

It’s 8mm shorter than the ZX-6R reference point, (and a whacking 60mm less the the Ninja SX), but there’s still room for a long swingarm within those dimensions, which promotes grip, natural anti-wheelie and stability.

The first seven corners (taken in third) are in quick succession, flicking left and right. The KB4 goes from one side of the tyre to the other with ease, the front Pirelli Supercorsa SP finding the apex without excessive effort. Bimota tweaked the Öhlins NIX30 fork and TTX36 shock from the cushy road setting to something firmer, and they provided ample support and feel despite the cool and slightly damp conditions of the day

Brembo Stylema radial calipers on 320mm discs offer more stopping than you’ll ever need – and the ABS can handle, certainly on track.

The final limitation is ground clearance. We rode two bikes – one with a standard exhaust system, another with the Arrow slip-on option. The carbon heat shield is the first thing to touch down, particularly on the stock pipe. The bellypan will skim the leading edges with the twin-stack Arrow cans allowing you a few more degrees of lean.

That’s as much as a result of the Bimota’s easy handling – what performance is has is easy to exploit straight away.

The 1043cc, 142bhp engine comes with the airbox, exhaust, fuelling and all electronic apparatus from the Ninja – including the Bosch cornering ABS.

Bosch engineers have adjusted the settings to suit the wildly different chassis specs of the KB4 compared with the Ninja donor bike, but it’s still conservative in its response for track use: you need to get just about all of your braking done upright, as any attempt to carry a lot of brake on turn-in (which the chassis could definitely handle) sees the anti-lock system interfere, causing you to run on.

The traction control also reaches the limits of its sophistication on track, even set to minimum. Try to drive out of corners on the side of the tyre, and the TC crackles and limits power output until you get close to upright, when it finally allows you to tap into the torquey delivery.

There isn’t a separate anti-wheelie setting, but it will allow the wheel to lift around a foot through the first few gears as you gas out of tight bends, managing the lift in a not-too-abrupt way, bringing the wheel down without sacrificing too much drive.

It's not a slow bike by any means, but the road-oriented power curve will be obvious in the company of 1000cc race replicas. Peak torque is at 8000rpm, peak power at 10,000. Just the point where a Fireblade, ZX-10R or the like is just getting going to deliver 5000-6000rpm of peaky power.

It’ll probably be just fine on the twistier UK circuits, where the spread of torque and gentler delivery will promote confidence in average trackday riders.

What are the connotations of the name Bimota? High-class chassis, with innovative design and beautiful finish? Or just another flaky Italian company, with patchy build quality and precarious financial security? Quite probably both.

Bimota owners take the rough with the smooth – they know ownership won’t be easy. But, what machines they are. Even the supposed duds are firm favourites with owners – the Mantra, with its Elephant Man looks is a sweet-handling, high-class alternative to the Monster 900 it shares an engine with.

Bimota’s fortunes were turned on their head in 2019, when Kawasaki bought 49.9% of the firm, bringing full technical support with them. Design and production remains in Rimini.

As well as the cash injection, Kawasaki’s parts support has given the near 50-year-old company a security and freedom to do what it set out to do: build better-handling, more beautiful motorcycles than mass production could ever hope to.

The bikes aren’t simply dressed-up Kawasakis: running gear and ancillaries aside, they’re distinctly Italian. Nearly everything is made in the Emilia-Romagna area: Brembo brakes come from Bergamo, the OZ  Racing wheels from a few hours north at San Martino di Luparti.

How the fit and finish would hold up to a winter of road salt is up for debate but the engine and electronics should be just as rock solid as they are on the Ninja.

The KB4 is a very special bike, bridging the gulf between friendly but mildly dowdy sports tourers, and superbikes with high-spec running gear but a power delivery not suited to the road.

Comfort, fuel range and other practical considerations are still unknown, but in dynamic terms it’s far better suited to the road than any WSB refugee, without compromising on spec, tech or finish. Yes, thirty grand is a lot of money, but in those terms it represents surprisingly good value for those with that much disposable cash. We never thought we’d say that about a Bimota.

It occupies a similar space to the Triumph Speed Triple RR and the MV Agusta Superveloce 800. These are sportsbikes that aren’t race replicas, with all the trappings those come with; peaky power, tall first gears, unyielding chassis that don’t deliver at ‘normal’ road speeds.

The KB4 has all the top-notch kit you expect on a premium sportsbike, and like Bimota’s flagship Tesi superbike, just about everything is carbon fibre or aero-grade alloy.

All the electronics are retained from the Kawasaki donor bike including ABS, traction control and the slightly disappointing dash readout – which looks out of place on such a special bike.

There’s no extensive parts catalogue brimming with factory doodahs and colour-coded whatsits like you’d get with a Kawasaki and it only comes in the red, white and gold paint you can see here.