Home News Ninja 400 Top Speed: A Speed Monster Sports Bike!

Ninja 400 Top Speed: A Speed Monster Sports Bike!

by Kelvin Yates

The Kawasaki Ninja 400 is a part of the 399 cc Ninja series of sportbikes. Kawasaki introduced it as a successor to Ninja 300. Its first launch was the 2018 model year. The main reason behind the replacement of Ninja 300 with Ninja 400 was the fact that Ninja 300 was struggling with Euro 4 emission standards compliance. Therefore Kawasaki replaced it with Ninja 400 for the 2018 model year. There were also significant upgrades in the engine, frame, suspension, and other parts. This produced a Ninja 400 top-speed sportbike.

The styling and design of the new Ninja 400 sportbike are like that of Ninja H2 and Ninja ZX-10R. It has chin-spoilers below the twin headlamps and a dashboard containing the information gauge similar to that of Ninja 650.

Despite having a large displacement, Ninja 400 is 17.6 lb. lighter than the Ninja 300. It also comprises a steel Trellis frame with the engine as a stressed member. This contributes towards a weight reduction of 13 lb. This sportbike also comprises LED headlights and taillights.

The engine comprises a large airbox for intake efficiency along with a downdraft air intake. The seat is 30mm lower than Ninja 300’s. This helps to improve the standover. Ninja 400 is available with ABS and comes equipped with a slipper clutch. The pull on the clutch is 20% lighter than that of the Ninja 300.

The suspension of Ninja 400 is stiffer than Ninja 300 with a large 41 mm fork. It also comprises 5 spoke wheels that are like those of Ninja 650. This contributes to low unsprung weight and better cornering stability than its predecessors.

Contents of this article entail;

Ninja 400 Top Speed: Design

When we compare Ninja 250 and 300, it looks like Kawasaki has decided that the only way to win the hearts of the American riders was to produce a sportbike for them. A sportbike to serve their riding need and improve their riding experience. This was to be fulfilled with the Ninja 400. By upgrading the displacement up to 399 cc, Kawasaki gave this sportbike enough power for both comfort and fun.

There has been an improvement in the bodywork of Ninja 400. This has made it better than its predecessors. It is made with big-bike features that are similar to those of H2 and 10R.

Ninja 400 comprises a split headlight designed in an angular shape. This compartment also mounts a vented bubble screen at the top. And chin spoiler incorporated with the vented engine cowl. The turn signals are also recessed to enable a clear look and easy penetration.

This angular design extends to the back through the tank. Then to the rest of the body producing a unique style. The handlebars are made in a rising design to enhance comfort. This also makes the vertical riding position possible. It also offers plenty of room to tuck in and throw your body around.

A narrow waist and saddle-to-tank union leave the rider with an easy shot from hip to ground and a functional seat. But there is no room for the passenger because of a small p-pad outback.

The taillights come mounted under the tail with a hanging-down turn signal or tag holder. Hugger and side-mount tags usually look better with the Ninja 400. The Metallic Matte Twilight Blue or Metallic Graphite Gray is sharp as a tack. The green and black KRT livery give the bike good ratings and mentions.

Ninja 400 Top Speed: Chassis

Kawasaki decided to tweak the frame on the Ninja 400 for a unique look overall. This was meant to accommodate entry-level riders so that they can navigate through the sportbike with ease. Just because you are a beginner you don’t have to struggle with Ninja 400.

The new Trellis frame is rigid enough in the right places for a nimble nature that delivers the expected handling to its fans. The eagerness in the corners is mainly because of the 24.7-degree rake and short, 3.6-inch trail.

Despite the shortened 53.9-inches wheelbase, the rectangular cross-section swing arm bears more length. This helps to reduce weight by directly linking to the engine or transmission assembly. This helps in eliminating a few of the frame components.

This seems to be an added advantage to some riders since Ninja 400 weighs almost 20-pounds less than Ninja 300. This translates into more nimble handling. Kawasaki nickel-and-dimmed the overall mass in several places to include the triple tree, wheels, and seat.

Ninja 400 is made of standard forks that float at the front end. Kawasaki opted for the non-adjustable, RWU front forks rather than the inverted or adjustable stems to keep production costs down. But the world is currently ready for tuneable suspension on lower-tier bikes.

The rear shocks come with a five-way preload adjustment. This makes it lick-a-windshield plain just like the front. It can disappoint, but not surprisingly.

At 362-pounds weight and 366 for the ABS models, the single 310 mm front disc is adequate with a 220 mm disc out back and twin-pot calipers all around it.

Cast alloy, 17-inch five-spoke wheels keep unsprung lower the weight. This mounts a 110/70 upfront and 150/70 outback to round out the rolling chassis.

Ninja 400 Top Speed: Drivetrain

Kawasaki engineers did some extra homework before designing the Ninja 400’s parallel-twin power plant. They did this even though their principal aim was not to build a super-fast engine. They still did some due diligence to focus on features that improved performance.

The Kawasaki drivetrain begins with a 70 mm bore and 51.8 mm stroke. This gives a 399cc displacement and flatter pistons which enhances compression to 11.5-to-1 with reduced squish area.

Oil jets help to cool the piston crowns from below. This makes them survive with a lighter construction for less reciprocating mass. There are also staggered intake funnels that smooth out torque generation with a larger airbox that helps increase volumetric efficiency. A tad that is oval-shaped with 32 mm throttle bodies manages fuel delivery.

What benefits do all these features give riders of the Ninja 400? For beginners, it gives them an easy to maneuver, a user-friendly performance that is manageable by all target groups.

The full 28 pound-feet of torque comes on at 8 grand with a slip-and-assist clutch to help limit back-torque. This prevents the loss of rear traction during aggressive maneuvers. There are no TC or rider modes for Ninja 400, but that is expected for sports bikes at this price range.

Ninja 400 Top Speed: Pricing

2022 is the base Ninja 400 sportbike that goes for $5,199 without ABS or $5,599 with ABS. The KRT Edition of Ninja 400 is available again for 2022 at $5,799 and is only available with ABS currently. Kawasaki provides a 12-month limited warranty to cover your Ninja 400. They can also extend this warranty up to 48 months.

Ninja 400 Top Speed: Competitors

Despite the improvements made on Ninja 400, it came much closer to Yamaha. But it has not yet overtaken the 321 cc YZF-R3 Yamaha entry-level sportbike.

Yamaha YZF-R3:

The Yamaha YZF-R3 is also built with a sporty appearance just like the Ninja 400. It possesses many of the same features just as Ninja 400. It also hits all the typical prime points with a vented engine cowl, minimal windscreen, and pillion pad.

The cosmetic distinctions are very minimal and only come down to personal taste, brand loyalty, and interest. Though they did brush up its plastic last year with details borrowed from its M1 race bike. This adds some curb appeal together with better penetration.

A steel-tube skeleton supports the R3 with KYB suspension components all around. It comprises plain vanilla stems with adjustable preload at the back as the only ride tweak. Yamaha falls short by just a tad in the brakes with a single, 298 mm disc up front. Though it also offers both an ABS and non-ABS model currently to choose from.

At 321 cc, Yamaha is overtaken by Kawasaki Ninja 400 with a concurrent power reduction. The R3’s mill cranks out 21.8 pound-feet of torque versus 28 pounds from the Ninja 400. This contributes to the biggest difference between the two competing sportbikes.

Despite the huge power difference, Yamaha still finishes very close to Ninja 400. This is at the checkout with a $5,299 sticker on the YZF-R3 with ABS.

Ninja 400 Overall Rating

The Kawasaki Ninja 400 is much more just like a modification to Ninja 300. It comprises more power and torque than the Ninja 300. It is also lighter, has a completely different chassis and ZX-10R appearance. The 169kg, 44bhp race rep is an A2 license favorite.


It’s easy to get on with, ultra-reliable, exciting, and a marked step up from the 300 in terms of performance and refinement. With a genuine 119mph top speed, 200-mile tank range, genuine big-bike character, and comfort. More experienced riders and commuters can enjoy the Ninja 400.

The old Ninja 300 struggled to get through the Euro4 emissions compliance. So its production had to be halted to pave way for the new Ninja 400. The new Ninja was packaged with greater performance than its predecessor from an all-new engine and chassis. This helped to reduce the weight by 8kg.

In September 2019, the Kawasaki company introduced new Kawasaki Racing Team colors for the Ninja 400 for the 2020 model year

Ninja 400 Ride, Braking And Handling

Kawasaki threw most of the features of the old Ninja 300 away and started afresh with the Ninja 400. It comprises an H2-Esque steel Trellis frame with a shorter wheelbase and longer swingarm. The swingarm is fixed to the back of the engine to save weight.

The Ninja 400 comprises non-adjustable 41mm diameter forks that are larger up from 37mm. 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 the overall weight of the curb. This helps save 4kg of weight. While the low 785mm height seat is unchanged, they made the seat 30mm narrower to help shorter riders to get their feet down.

Ninja 400 Engine And Performance

With its extra 103cc and modified airbox and intakes, Kawasaki teases power up from 39bhp to 44bhp. They achieve this from its heavily mudded A2 license compliant 399cc, 8v liquid-cooled parallel twin-cylinder engine.

There is also improved torque by 40%, up from 19.9lb-ft to 28lb-ft. There is also a revised slip and assist clutch. The Kawasaki Ninja 400 top speed was 100mph with a following wind.

Ninja 400 Reliability And Build Quality

The built quality, fit, and finish have been raised above par for the Kawasaki premium models. Reliability and durability are things that you don’t have to worry about. The only thing that you can look for when buying a used Ninja 400 is the general condition and full-service history.

Kawasaki Ninja 400 owners’ reviews show very positive reports. There are no build quality complaints reported.

Ninja 400 Top Speed: Equipment

The revised styling for Ninja 400 borrows its LCD gauges from its Ninja 650. 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 advantageous for many, you don’t have to be worried if you’re over six feet tall. The Kawasaki also offers 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.

Ninja 400 0-60 Mph In 4.14 Seconds

Kawasaki’s Ninja 400 was introduced into the market in 2018. Since then it has replaced the largely capable and popular Ninja 300. The Ninja 300 was also a replacement for the Ninja 250. Ninja 400 was likely Kawasaki’s response to Yamaha’s YZF-R3. Yamaha had an edge far above Ninja 300 in terms of engine performance.

The need to accommodate the ever-changing motorcycle learner laws and restrictions in many markets inspired the decision to design a bigger version of the 300. This was also a response to competitors offering faster and more powerful class alternatives.

The Ninja 400 engine was much the same as that of the 300 it replaced. The only difference is it got a significant boost in terms of capacity up from 296 cc to 399 cc.

There was also a peak claimed the power of 49 hp at the crank compared to 35 hp at the crank for the Ninja 300. This was a celebrated boost to Kawasaki fans and those 300 owners who may have wanted to upgrade. The amount of torque was also up to 28 lb/ft.

The larger engine of the 400 ensured that the Ninja 400 was more tractable and was less dependent on gears and rpm to make effective overtakes. This means that the Kawasaki Ninja 400 almost had the feeling of a big bike. Thanks to the larger engine that the 300 never offered.

The new Ninja 400 makes a respectable 44 horsepower at 10,500 rpm which is very impressive. This is not anywhere far off Kawasaki’s claim of 49 hp at the crank.

The Rule

When power is transmitted from crank to wheel the average chain-driven motorcycles will lose around 10-12 % of their power. It happens through transmission losses caused by friction and heat and the effort to spin the rear wheel.

This contributes to rear-wheel horsepower figures differing from those of the actual manufacturer’s claims at the crank.

The Ninja 400 in terms of power is at the same level as Honda’s CBR500R as the main challenger despite having a small capacity engine.

What also captivates is that the little banging parallel twin produces over 40 horsepower from 8000 rpm and carries this to 12,000 rpm.

This spread of power makes the Ninja 400 less shift-dependent as you can still make good progress without having to scream the engine to 12,000 rpm. This is something that you had to do often on Ninja 300 variant. It was hard work and tiresome.

Widespread peak power is also vital because it allows you to hold on to gears for a little longer in corners. Additionally, the engine is relatively flexible as right from 3000 rpm the Ninja 400 is making more torque. More than what the 300 Ninja could produce at its peak.

The broader finishing makes the Ninja 400 provide the feeling of a big bike. Its performance also portrays it like a big bike. This is according to the numbers it puts down.

Ninja 400 Top Speed And Acceleration Review

With more power and with a relatively lightweight of 169 kg the little 400 is pretty quick. This is a significant step above the Ninja 300 which is a little heavier at 172 kg.

The Ninja 400 can accelerate from 0 to 60 mph is at 4.14 seconds. This is still slightly slower than one of its bigger capacity rivals the MT-07. Though it is very close considering the displacement disadvantage the Ninja 400 has.


A sub 5 second 0-60 mph time is significantly quick at any standard. This is as fast and sometimes faster than many hot hatches and sports cars.

Acceleration Comparison

A lot of smaller capacity motorcycles in this class can all accelerate to 60 mph in around 6 seconds. Or under with the Ninja 300 at around 5.4. But as speeds increase their acceleration decreases.

Though the Ninja 400 is still more effective above this speed. Ninja 400 can still clock 0-100 mph in a time of 11.8 seconds. This is a mighty impressive time. It is over 6 seconds faster to the same speed as Ninja 300.

Ninja 400 achieves 60 mph to 100 through the gears comes up in 7.75 seconds. While the Ninja 300 lags significantly at 12.80 seconds. This means that the Ninja 400 can get from 0 to 100 mph faster than the Ninja 300 can accelerate from 60 mph to 100 mph.

Ninja 400 Top Speed

With all smaller capacity lower power motorcycles seeking their maximum speed, this may require a significantly long piece of tarmac to hit this kind of speed.

To achieve its ultimate top speed of 116 mph the Ninja 400 needs 100 seconds and around 4.8 km. Though this cannot be a fair analysis. This is simply because Ninja 400 can achieve 111 mph in around 20 seconds at around 750 meters from the stopping point.

It is only that the last few mph requires a significant amount of time and distance.

The Ninja 400 is an exceptional motorcycle for beginners. It is economical with affordable motorcycle insurance. It is also a capable sportbike even for more experienced riders.

With it, you get outstanding straight-line performance which is a significant step above the Ninja 300. You may also look at other class competitors such as the Honda CBR650R full power, or the restricted CBR650R and CBR500R.

Ninja 400 Top Speed Summary

The Kawasaki Ninja 400 uses a 399cc twin-cylinder engine with 45bhp. Using a new downdraft intake which is accompanied by a larger airbox offers enhanced intake efficiency.

The new Ninja 400 uses an assist & slipper clutch. This requires much less pressure at the lever. This makes city riding a much easier experience. It gives more control on the down change preventing the possibility of the rear wheel locking up.

The Ninja 400 offers considerable weight reduction over Ninja 300. This is attributed to its new chassis, suspension, and engine. These components also provide enhanced stability and maneuverability.

With the latest ABS unit from Nissin, clamping down on a 290 mm semi-floating disc, the Ninja 400 will stop as well as it goes.

A seat height of just 786mm makes the Kawasaki Ninja 400 very accessible to most riders. There is also an ERGO-FIT higher seat for the taller riders.

LED headlights light up the path of the Ninja 400. They also add a stylistic appearance to the lightweight superbike. They borrowed the speed assembly from the Ninja 650.

The Ninja 400 is also fitted with a 14-liter fuel tank that can offer over 200 miles of range.

The styling of the Kawasaki Ninja 400 with aggressive-looking headlamps and nose cowl, and a minimalist rear seat unit makes it a real “Ninja”. The bike shares so many of its looks with the ZX10R. Extra “volume” has been designed into the bodywork to give this lightweight machine one much larger look.


The big bike looks make this a credible step into the Kawasaki brand. The handling and performance of the Kawasaki Ninja 400 will keep you interested for years to come.


ERGO-FIT is an interface system that allows a wide range of riders to feel at one with their machine.


ABS (Anti-lock Brake System) ensures stable braking performance by preventing wheel lock during braking.

Assist & Slipper Clutch

Based on racing technology, the Assist & Slipper Clutch acts as both a back-torque limiter and a self-servo mechanism that enables a lighter clutch lever pull.

Economical Riding Indicator

The Economical Riding Indicator is a mark appearing on the instrument panel to indicate favorable fuel consumption, encouraging fuel efficient riding

Ninja 400 Top Speed: Conclusion

The Kawasaki Ninja 400 comprises a lineup of fast and powerful motorcycles. They are sports bikes that are built to serve the need of those who enjoy going out on speed sportbikes.

The name Kawasaki Ninja 400 is a very important name to the Japanese since it is derived from the most famous stealth warrior of Japan. So, if you are a person who enjoys speed and strength then the Ninja 400 sportbikes would be the best option for you. This is a durable and reliable speed bike that will serve you for years with lots of fun.

The Ninja 400 is believed to be a classic motorcycle for beginners since it comprises easy-to-ride features that allow riders of different experiences levels to simply jump on it on the go. This Japanese sportbike looks good, rides well on the road, and is also comfortable to ride over long distances.

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1 comment

Sonalika 50 Hpq March 3, 2022 - 8:58 am

Nice bike, very stylish and best specifications.


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