KAWASAKI NINJA 400 (2018 - 2021) Review


  • Well-built and reliable
  • Simple to ride
  • Big A2 licence thrills

At a glance

Owners' reliability rating: 4.9 out of 5 (4.9/5)
Annual servicing cost: £250
Power: 44 bhp
Seat height: Medium (30.9 in / 785 mm)
Weight: Low (370 lbs / 168 kg)


New N/A
Used £4,400

Overall rating

Next up: Ride & brakes
4 out of 5 (4/5)

The Kawasaki Ninja 400 is much more than a facelifted Ninja 300. Not only does it have more power and torque, it’s lighter, has a completely different chassis and ZX-10R looks.

The 169kg, 44bhp race rep sportsbike is an A2 licence favourite. It’s easy to get on with, ultra-reliable, exciting and a marked step up from the 300 in terms of performance and refinement, but with a true 119mph top speed, 200-mile tank range, genuine big-bike character and comfort, the Ninja 400 can be enjoyed by more experienced riders and commuters, too.

The old Ninja 300 couldn’t haul itself through Euro4, so was killed off to make way for this new Ninja 400, boasting greater performance than its predecessor from an all-new engine and chassis – the net effect being a claimed weight saving of 8kg.

In September 2019, the firm introduced new Kawasaki Racing Team colours for the Ninja 400 for the 2020 model year. You can see the new livery below.

Kawasaki Ninja 400 in Racing Team livery for 2020

For 2024 the Ninja 400 is replaced by the Kawasaki Ninja 500.

Additional reporting by Martin Fitz-Gibbons and Adam Child

Ride quality & brakes

Next up: Engine
4 out of 5 (4/5)

Kawasaki threw most of the old Ninja 300 in the bin and started again with the Ninja 400. It has an H2-esque steel trellis frame with a shorter wheelbase and longer swingarm, fixed to the back of the engine to save weight.

Non-adjustable ‘right way up’ 41mm diameter forks are chunkier (up from 37mm) and the twin piston front brake caliper now bites a 310mm petal front brake disc (up 20mm) taken from a ZZ-R1400. Lighter wheels contribute to an all-up kerb weight saving of 4kg and while the low 785mm height seat is unchanged, its 30mm narrower seat helps shorter riders get their feet down.

MCN tester Jon Urry says: "Thanks to its improved chassis, light weight and 17- inch tyres corners are a joy. Despite being softly sprung, the suspension responds better than you’d expect on a bike of this price, however the motor’s extra performance would justify a second front disc."

Fellow tester Martin Fitz-Gibbons also remarks: "Everything about the Ninja 400 feels welcoming, helpful and accessible. The hardest thing is adjusting the mirrors, which are mounted just beyond easy reach. Low-speed balance is exemplary. Suspension is soft and springy but gives a generally decent ride. Steering is sharp, light and stable, and there’s plenty of ground clearance. Dunlop GPR300 tyres are a big step on from the dire IRC Road Winners that blighted previous mini-Ninjas. The two-piston, single-disc front brake is average though — it bites gently and needs a strong squeeze to stop quickly."

Watch: Kawasaki Ninja 400 on Brands Hatch Indy circuit with Michael Neeves


Next up: Reliability
5 out of 5 (5/5)

With its extra 103cc and modified airbox and intakes, Kawasaki have teased power up from 39bhp to 44bhp from its heavily-modded, but still A2 licence compliant 399cc, 8v liquid-cooled parallel twin-cylinder engine. Torque is also increased 40%, up from 19.9lb-ft to 28lb-ft and there’s a revised slip and assist clutch. The Kawasaki Ninja 400 top speed was 100mph with a following wind.

Jon Urry says: "Far from lacklustre the Ninja’s acceleration is brisk and speeds of 100mph are possible, making it the quickest bike in its class. The parallel twin packs a wide spread of torque, so you aren’t continually dancing on the gear lever, the throttle action is beautiful and it even sounds spirited. The gearbox is precise and the clutch light – it’s a genuine surprise just how much fun the Ninja 400 is."

Martin Fitz-Gibbons agrees: "Where the 300 needed thrashing, the 400 feels full-bodied and forgiving. Fourth gear chugs hard from less than 20mph yet revs out at more than 100mph. The clutch lever has an ultra-light action and the fuelling is faultless".

Reliability & build quality

Next up: Value
5 out of 5 (5/5)

Built quality, fit and finish are up there with Kawasaki’s premium models. Reliability and durability aren’t issues, so the only thing to look for when buying used is general condition and a full Kawasaki service history.

Our Kawasaki Ninja 400 owners' reviews show very positive reports, with no build quality concerns reported. One buyer thought the brakes aren't up to much, but this is contradicted by the rest of the entries.

Value vs rivals

Next up: Equipment
4 out of 5 (4/5)

The Kawasaki Ninja 400 is in the same general price bracket as the A2 licence rivals like Yamaha’s R3, KTM RC390 and class-leading Honda CBR500R (there’s no substitute for cubes).

Running costs are, on the whole, pretty low. The small-capacity motor means road tax is cheap. Slim crossply tyres don’t cost much and last ages. Even thrashed hard the motor still returns over 60mpg, and with a less-frantic right hand you could see 75mpg. That’s fairly good – though perhaps not astonishing compared with a Honda NC700, a Yamaha MT-07 or even a gently ridden ER-6f, all of which offer similar economy despite having twice the capacity.

Insurance-wise it’s comparable to natural rivals such as the Yamaha YZF-R3. One detail that may be worth bearing in mind is that the Ninja 300’s ignition barrel doesn’t have an immobiliser, whereas the Honda CBR500R does.

Private sales start at just over £2000, with dealer sales around £2500 – but the price window is very narrow, with even the most expensive bikes topping out around £3000. Prices seem to be very slightly lower than a Yamaha R3 or KTM RC390 for a similar age and mileage.

However, there is one fly in the low-cost ointment. The Ninja’s official service schedule includes valve clearance checks every 7600 miles. That’s a £300+ job at a franchised Kawasaki dealer. And with that in mind, it’s unsurprising that many valve checks get skipped, or a seller will (claim to) have done the work themselves. Always check, and look for proof, when valves were last inspected.

MCN group test: Kawasaki Ninja 400 vs Honda CBR500R vs KTM 390 Duke

First published in MCN on 16 May 2018 by Adam Child

Kawasaki Ninja 400 vs KTM RC390 vs Honda CBR600R

There are many reasons why the Kawasaki should win this test. It’s the quickest, therefore the most fun. Most preferred its sporty looks and it handles far better than its price suggests. But the catch is that it doesn’t have the all-round capabilities of the Honda. The CBR feels like a bigger bike. Its dimensions are normal-size and it’s comfortable, refined, and smooth, offering a huge tank range and excellent fuel economy. If I had to pick one bike to do it all again, I’d pick the CBR. The KTM is tempting, fun and punchy and more importantly it’s over a grand cheaper than the Honda, but if you want a bike for daily use and long trips it falls behind. The Honda wins.


4 out of 5 (4/5)

As well as its revised styling the Ninja 400 borrows its LCD clocks from its Ninja 650 big sister and it comes with ABS as standard. Optional extras include a tank bag, tall screen, 12v socket and rear seat cover.

While the Ninja’s low seat will be a boon for many, fear not if you’re over six-foot tall as Kawasaki also offer a taller seat option that adds an extra 30 mm. Ninja 400 Performance model also comes with a tank pad, pillion seat cover and road legal Akrapovic end can.

You can order the Kawasaki Ninja 400 in two colours - standard, or the KRT Race replica livery.


Engine size 399cc
Engine type Liquid-cooled, 8v, parallel twin
Frame type High tensile steel trellis
Fuel capacity 14 litres
Seat height 785mm
Bike weight 168kg
Front suspension 41mm, non adjustable
Rear suspension Single Uni-Trak shock, adjustable preload
Front brake 1 x 310mm petal disc with dual piston Nissin caliper
Rear brake 220mm single petal disc with dual piston caliper
Front tyre size 110/70 x 17
Rear tyre size 150/60 x 17

Mpg, costs & insurance

Average fuel consumption 72 mpg
Annual road tax £55
Annual service cost £250
New price -
Used price £4,400
Insurance group 9 of 17
How much to insure?
Warranty term Two years

Top speed & performance

Max power 44 bhp
Max torque 28 ft-lb
Top speed 100 mph
1/4 mile acceleration -
Tank range 240 miles

Model history & versions

Model history

  • 2019: Kawasaki Ninja 400 introduced, replacing Ninja 300. Bigger engine with more power and torque, new tubular steel chassis, uprated suspension, revised steering geometry and ZX-10R inspired styling and graphics.
  • 2021: Bike goes off sale.

Owners' reviews for the KAWASAKI NINJA 400 (2018 - 2021)

9 owners have reviewed their KAWASAKI NINJA 400 (2018 - 2021) and rated it in a number of areas. Read what they have to say and what they like and dislike about the bike below.

Review your KAWASAKI NINJA 400 (2018 - 2021)

Summary of owners' reviews

Overall rating: 4.8 out of 5 (4.8/5)
Ride quality & brakes: 4.2 out of 5 (4.2/5)
Engine: 4.9 out of 5 (4.9/5)
Reliability & build quality: 4.9 out of 5 (4.9/5)
Value vs rivals: 4.8 out of 5 (4.8/5)
Equipment: 4.7 out of 5 (4.7/5)
Annual servicing cost: £250
5 out of 5 Great Bike
23 June 2023 by Rich

Version: KRT

Year: 2021

Great little bike. Faster than you might think, screams like a good 'un when heading towards the red line, plenty comfy enough for an hour and a half before taking a break (I'm 6 foot and it fits me fine), 60+ MPG and a doddle to move around due to dimensions and weight. I was looking for a smaller bike as I'm not getting any younger, done fast bikes now, but wasn't ready to go down the Royal Enfield route if you know what I mean, so having enjoyed owning a little R3 a few years ago I thought the Ninja would suit the bill. Certainly not disappointed. Don't be put off by the sporty looks, the riding position is relaxed and comfy. Probably not the bike to take you touring in the Alps but great for short and medium trips out. I did 4 hours non-stop around Snowdonia last week and it was great fun and no need for a chiropractor when finished.

Ride quality & brakes 4 out of 5

Handles brilliant, can really get a move on and feels solid and stable. Brakes are fine but last bike had Brembo Stylema's so don't feel that good in comparison but once you used to them no problem.

Engine 5 out of 5

Superb. Revs like mad, usable torque once spinning, gearbox super smooth.

Reliability & build quality 5 out of 5

2000 miles completed so far this summer and hasn't missed a beat. Looks and feels solid and well made.

Value vs rivals 5 out of 5

Free first service, so can't say but MPG and consumables commensurate with smaller bike.

Equipment 5 out of 5

Nice mix of analogue & digital dash. Great to have a proper rev counter after that ludicrous attemp on previous Triumph Tiger.

Buying experience: Bought from A&D Denbigh, happy with deal which included a bit of discount and a complimentary first service. Excellent buying experience, will be happy to buy there again.

5 out of 5
09 May 2023 by coltonswat

Version: KRT

Year: 2021

Annual servicing cost: £250

Absolutely love this bike.

Ride quality & brakes 5 out of 5

You can ride many hours before needing a break, clutch is light so new riders will have an easy time.

Engine 5 out of 5

Power on this bike is great for its class, and competes with some 500s on the road, and can take on just about anything at the track. being able to use your full power is a huge benefit.

Reliability & build quality 5 out of 5

High quality, easy to learn on.

Value vs rivals 5 out of 5
Equipment 5 out of 5
5 out of 5
12 October 2021 by Caddy69

Year: 2021

What a bike

Ride quality & brakes 5 out of 5
Engine 5 out of 5
Reliability & build quality 5 out of 5

Top notch

Value vs rivals 5 out of 5

Yeah if your a fuel Needle watcher Then this is it

Equipment 5 out of 5
5 out of 5 Just a superb little bike
30 August 2021 by Graham Dunsmore

Version: KRT

Year: 2018

Having 50 years biking under my belt and owning a multitude of bikes from CB175 to 1 liter sports bikes, this little bike has to to rank as one of the best I've ever owned. At 5' 6" and slim build, the ergonomics are spot on for me. It is in fact the most comfortable bike I've had in years and that includes the seat. Unless you plan to do highly illegal speeds, the performance is very good for a small bike. It will cruise effortlessly at motorway speeds and handling is excellent with great stability, there is no need for a steering damper! It of course excels in the twisties. With me weighing only 9.25 stones, the suspension works well at controlling the bike but the rear can be a bit harsh at times. I will prob fit a Nitron shock. I have fitted a Lextek end can and a K & N filter. Fuelling seems excellent with a little performance gain and of course sounds so much better. Overall it is just such a fun bike. My previous bike was an ER6, my choice out of the two would def be the ninja 400.

Ride quality & brakes 4 out of 5

I'd say a great all round bike. 2 hours riding before needing a break. I would happily tour on this bike, obviously with limited luggage carrying capacity although there are panniers available for it..

Engine 5 out of 5

MCN would appear to have got it wrong re valve clearance check. The owners manual states every 26,250mls. Brilliant little engine. Very flexible with good mid range power and good power up the top end. I have no problem staying with larger bikes unless as stated you wish to travel at very illegal speeds! My light weight no doubt helps with acceleration..

Reliability & build quality 5 out of 5

Build quality appears very good with no corrosion although I do look after my bikes well.

Value vs rivals 5 out of 5

£45 road tax and over 70 mpg, what's not to like..

Equipment 4 out of 5

An aftermarket double bubble screen makes motorwat speeds relaxing. The engine doesn't sound or feel buzzy like many inline fours do at 70 - 80mph. Never any mirror blurring.

Buying experience: Dealer, £3989. 3905 miles. Now over 8,000 trouble free miles.

5 out of 5 Get one
30 April 2021 by Rab

Version: Krt

Year: 2019

Great little bike great gear changes practically goes itself so well balanced.

Ride quality & brakes 4 out of 5

Seat gets uncomfortable after 2 hours you have to get off and walk round abut.

Engine 5 out of 5

No issues runs a dream

Reliability & build quality 5 out of 5

Never had any issues

Value vs rivals 5 out of 5

£12 to fill tank does 150 miles.

Equipment 5 out of 5

Manoeuvre ability

Buying experience: 5500 and paid 5700 for racing colours and abs

4 out of 5 A great reason to go green
19 March 2021 by Mad Dog

Year: 2020

Would have been ☆☆☆☆☆ if not for the inexplicable routing of the exhaust system.

Ride quality & brakes 4 out of 5

It is a 400, so do not expect the breaking power of an H2 or ZZR, but they are up to the job.

Engine 5 out of 5
Reliability & build quality 5 out of 5
Value vs rivals 5 out of 5
Equipment 5 out of 5

Top end of the A2 range and good enough to continue using post A2 test.

Buying experience: From local dealer Bridge Motorcycles in Devon. Not only a good deal, from a team who are customer focused, but also the added benefit of a lifetime warranty.

5 out of 5 A Welcome Surprise
02 July 2019 by RhysC

Version: Ninja 400 Performance

Year: 2019

Bought this bike 3 weeks ago as my third bike (Already have a Kawasaki Ninja 650 and H2 SX). Always been a fan of small capacity lightweight sports bikes and the Ninja 400 replaced a Ninja 250SL. This bike is definitely more than I expected it to be, it's as fast as you really ever need. It is very light and flick-able and really makes you giggle when riding although equally is easy to ride in traffic and if your'e in the mood for an evening chill ride. mpg currently just over 70 so you really can't complain. My only niggle with the bike is that the seat is a bit hard, it's not uncomfortable but really isn't what I'd call a long distance seat. Drayton Croft Kawasaki in Hinckley have supplied all three of my bikes and it was on their recommendation I looked at the 400, definitely glad I did. I hear the Ninja 400 constantly called a beginners bike and while it is great for you to start your sports bike journey on it is so much more than that. I would suggest any seasoned riders out there looking for something small and or a second bike to play on to seriously consider this bike and it is 100% worth a test ride.

Ride quality & brakes 4 out of 5

Overall not bad at all, handles bumps ok, possibly a bit soft for some but I don't have issues. Not a bike I would take a pillion on even though it is possible.

Engine 5 out of 5

No problem at all here, smooth and quiet when your'e not in the mood and a great sound when you are, I have performance model so has Akrapovic exhaust is standard which helps. Engine pulls in all gears and is flexible even at low speeds, there is a definite surge around 7k and pulls well all the way through to the red line. Although motorway speeds are easily obtained, 6,700rpm at 70mph means its not really a long distance motorway cruiser.

Reliability & build quality 5 out of 5

Only had the bike for a short period so hard to tell but if my other two bikes are anything to go by then all will be good

Value vs rivals 4 out of 5

Again, a bit early to say and let's face it we'd all like to pay as little as possible for a bike and servicing, but price is on par with rivals and I've always had a great deal.

Equipment 4 out of 5

Very back to basic bike apart from adjustable rear suspension but it is expected. Would like it if brake leavers were adjustable, not a real problem, but then I have fairly big hands, may be an issue if your hands are on the small side.

Buying experience: Always have great service from Drayton Croft in Hinckley and always a great deal. Always friendly and I would always buy a bike from main dealer. Have to say though not all Kawasaki dealers are equal, I ride 44 miles to them because dealers near me in Worcestershire leave a lot to be desired.

4 out of 5
11 April 2019 by Jaco Krige

Year: 2019

I would definitely recommend the bike to any beginner or lady rider. It is very economical and a stunning bike that you won't get bored with quickly.

Ride quality & brakes 3 out of 5

The ride is smooth and comfortable, but the brakes are not as good as I would like them. If you have to ride fast you will not stop it quick in an emergency.

Engine 5 out of 5

More than enough power for the beginner and good power delivery when changing gears in mid range revs.

Reliability & build quality 5 out of 5
Value vs rivals 5 out of 5
Equipment 5 out of 5

The ABS brakes is a big plus on the bike for safety. I would definitely invest in some steering damper, cause the bike is moving too much over the road with every small movement you make on the bike.

Buying experience: The dealer was very thorough with explaining all the details and features of the bike.

5 out of 5 Fantastic beginner bike!
02 June 2018 by Chris

Year: 2018

Ideal first bike!

Ride quality & brakes 5 out of 5

A very decent all rounder. My first bike, very pleased with it. Lovely to ride, predictable and feels spot on in the bends, love it!

Engine 4 out of 5

All good so far, fast enough to entertain but not stupidly quick, spot on for a newbie like me!

Reliability & build quality 4 out of 5

So far so good!

Value vs rivals 4 out of 5

Averaging around 65mpg!

Equipment 4 out of 5

Nice layout, switch gear etc. Gear indicator, fuel range & mpg nice to have!

Buying experience: Bought new from Kawasaki Dealer, no complaints.

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