QJMotor SRK 421 RR (2026 - ) review

The SRK 421 RR is one of the latest offerings from QJMotor, a name still new to the UK scene though growing in recognition off the back of a rush of its models hitting the roads here. As with others we’ve tested recently, one of its most appealing features is its price-defying spec and style. That’s due largely styling input from C-Creative – the Italian consultancy set up by British designer Adrian Morton and ex-MV Agusta CEO Giovanni Castiglioni. So, if you spot shades of MV Agusta in the SRK’s lines it’s not entirely coincidental. That said, the SRK is still not quite as slick and sporty as, say, Kawasaki’s ZX-4RR, it’s not a ‘mini-RC30’ or similar from those heady days of 90s grey imports and nor does it carry that weight of history. For all that the SRK is a genuine four-cylinder sports bike with Brembos, Marzocchis and more, looks great, comes in three different colourways and costs less than six grand! What’s not to like!

Yes, the SRK 421 RR is a junior four-cylinder sports bike but, thankfully, not as extreme and single-minded as that suggests. The clip-on bars are set relatively high while the footpegs, although sportily high, are not too cramped, even for your 6’ 3” tester. It’s also light at just 185kg wet, relatively slim for a four-cylinder bike and with an accessibly low 795mm seat. Overall, it’s not at all bad, especially for a 400 supersports.

400 supersports were traditionally very specialised machines built to deliver screaming performance at sky-high revs in combination with nimble handling and mini superbike thrills. Suffice to say, long-distance comfort, weather protection and capacity for carrying a pillion and/or luggage was never on the agenda. Saying that, the format remains appealing for younger, less experienced riders and – hunger for revs aside – isn’t as extreme as you might expect. And the SRK 421 RR is a good example of that. As above, the riding position isn’t as hardcore as it might have been while the lack of weight and all-round manageability make it a better commuter than you might have credited. OK, we’re possibly clutching at straws slightly and the SRK remains a single-minded machine. But one with a broader operating window than the looks and spec suggest.

At the heart of the SRK 421 RR is a 421cc transverse four-cylinder, twin-cam, 16-valve motor designed in-house by QJMotor. As you might expect it needs revs to deliver its best, the oversquare format meaning the impressive 77 horsepower available comes at a heady 14,000rpm, the peak torque of 39Nm not that far behind. On-paper that’s on a par with the more exotic (and expensive) Kawasaki ZX-4RR, though the SRK can’t match its Japanese rival for refinement and our test bike was noticeably ‘fluffy’ at lower revs. It felt a lot better in its comfort zone higher up in the rev range, though. Brakes are more than up to the job, meanwhile, the chunky twin front discs grasped by radially-mounted Brembo calipers and assisted by conventional dual-channel ABS.

QJMotors’ bikes impress with the quality of their cycle parts, the Brembo brakes mentioned above paired with premium suspension components from fellow Italian brand Marzocchi. True, these are built under licence in China as part of a partnership deal but there’s no doubting the quality while the range of adjustability is likewise impressive, with compression and rebound for the fork and preload and rebound for the monoshock rear. A short wheelbase and sharpish steering geometry combined with the overall lack of weight make it a teasingly nimble little bike, too. True, the set-up is perhaps not quite as refined overall as its more thoroughly developed rival from Kawasaki. But it’s more than good enough to stand a first proper sports bike, and there’s headroom for further fine-tuning to suit your tastes and riding style.

The headline feature of the SRK 421 RR is, of course, its bargain price and huge saving over the seemingly similar Kawasaki ZX-4RR. But it’s not the end of the story. Although modest in capacity the SRK’s engine is still a revvy little unit, which is bad news for fuel consumption and demands on brakes, tyres, chains and the rest. Depreciation is another unknown quantity given how new both bike and brand are to the market, and what you save upfront may bite you down the line when you come to sell it on.

Like other QJs call this a holding score for now, based on the fact the brand and its bikes are simply too new to the UK market to really have a sense of its reliability. We’re hopeful, though, for the fact QJMotor has been building bikes for a lot longer back in its home market so is now beginner in engineering terms. Build quality looks decent, the cycle parts are all top drawer and from recognised suppliers and we’re hopeful it should prove to be dependable.

Another ‘suck it and see’ consideration when it comes to choosing a Chinese bike over something from a more familiar name, given the standard two-year warranty is really the bare minimum these days. Once the initial 500-mile break-in service has been done intervals come round every 6,000 miles or annually, which sounds short but probably isn’t too much of a worry on a bike of this nature.

If QJMotor can’t quite compete on things like warranty, service intervals and a proven reliability record it certainly aces it on standard equipment, especially at this price. As mentioned, Brembo brakes and Marzocchi suspension are a welcome sight at this level, these matched with a slick 5.0-inch TFT dash, LED lighting, switchable rider modes and electronic support systems and even tyre pressure monitoring. All of which are truly impressive.

Four-cylinder 400 supersports remain a niche proposition, partly explaining why they’d all but disappeared. But they still have a lot going for them, given they’re a fantastic first step into four-cylinder sports bikes, more fun to ride than their bigger equivalents at speeds you can enjoy on the road and more accessible. Much more at this price! True, it can’t match the equivalent Kawasaki for polish or refinement. But nobody’s going to quibble at this price!