The California Air Resources Board has issued an executive order certifying a 2018 Kawasaki Ninja 400 with a 399cc engine. The certification confirms what we assumed earlier this year after a local television news program aired a story about Kawasaki filming a commercial in Milwaukee, revealing the Ninja 400 name.

Related: Oops! Milwaukee News Crew Outs 2018 Kawasaki Ninja 400

Since that story broke, Kawasaki announced most of its returning 2018 U.S. models, which noticeably omitted the Ninja 300. We can now safely assume that the new Ninja 400 will be replacing the 300 in Kawasaki’s lineup as its entry-level sportbike.

The new Ninja 400 continues a trend of beginner bikes growing larger and larger in recent years. The 249cc Ninja 250 had been around for years, and you can still regularly find them on the used bike market long after it was replaced in 2013 by the Ninja 300. The impetus for that displacement increase was the introduction of a new rival in the Honda CBR250R. Since then, the Ninjette has seen more new rivals sporting even larger engines in the KTM RC390 and the Yamaha YZF-R3. Honda’s CBR250R was later replaced by the CBR300R (and hopefully soon, a larger version of the new CBR250RR currently offered in Asia). It’s also likely just a matter of time before BMW puts its G310 motor in a fairing. Apart from the late-to-the-party Suzuki GSX-250R and offerings from smaller manufacturers like Hyosung, the entry-level sportbike market has long outgrown the quarter-liter displacement that thousands of new riders started out on for years.

The CARB document certifies two model codes: EX400GJ and EX400HJ. All of Kawasaki’s previous small-displacement Ninjas used the EX designation, so this is clearly for the Ninja 400. The J at the end stands for the 2018 model year and the G and H letters likely signify color options, likely green (G) and white (H).

While the CARB certification confirms the engine displaces 399cc, the document does not tell us how it reaches that size. Kawasaki had previously produced a Ninja 400 in Asia (and briefly, Canada) that was essentially a smaller version of the Ninja 650’s powerplant but it’s more likely we’re looking at either a sized-up version of the Ninja 300’s engine, if not a new motor all-together.

To keep costs manageable for the beginner market, Kawasaki is likely keeping its littlest Ninja a Twin, so those hoping to see a small-displacement Inline-Four will have to keep dreaming. Increasing the 300 engine’s bore from 62.0 mm to 72.0 mm while keeping the stroke at 49.0 mm will produce a 399cc engine, but a more moderate increase in piston size combined with a longer stroke may be more likely.

With a 399cc displacement, the 2018 Kawasaki Ninja 400 qualifies for Japan’s sub-400cc license class, so it’s possible we’ll see it next week at the Tokyo Motor Show. It’s more likely, however, that Kawasaki will wait for EICMA next month. As always, Motorcycle.com will have the latest information as it becomes available.

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  • Matt O

    I hope this is based off the 300. As a guy that jumped right from the msf to a ninja 500 I think a bike with that light weight and about 40-45 hp would be perfect.

    • Rocky Stonepebble

      That EX500 was a fine bike. Great for beginners and veterans alike.

  • spiff

    I think this is a good starter bike engine size. Something friendly enough to learn on, but fast enough to entertain once you have the basics down.

    With all the computer technology I am surprised no one has put out a 650 with a beginner mode. A Z650 is compact enough to not be intimidating, add a beginner mode, and you have a bike you won’t out grow. My first 4wheeler had an adjustable throttle stop. Heck I use rain mode on myself when the opposite is needed.

    • SteveSweetz

      Come on, what beginner wouldn’t turn off beginner mode in like 2 weeks? I certainly would have.

      In countries with tiered motorcycle licensing, most of the Japanese manufacturers do sell throttle restricted versions of their 650cc bikes, but they’re not so easy to de-restrict anymore due to the very reason I mentioned above.

      • spiff

        I had to pay to get certain features unlocked on my bike. If self restraint isn’t enough, then there would still be options with available technology.

    • Tim Sawatzky

      My wife learned to ride on a Ninja 650 and did just fine without a beginner mode. It’s a great bike to learn on and very easy to keep in the safe zone while learning. Maybe it’s more that she had no desire to “see what it could do”. But respected the bike’s power. Unlike me when I rode it.

  • HazardtoMyself

    Maybe it is after seeing the mosquito article, but even though unlikely hoping Kawi brings this to market with their ergo system like the Vulcan S.

    • spiff

      The Vulcan S is pretty slick with it’s ergo set up.

    • spiff

      MO should do a shootout between the Vulcan S and the Rebel 500.

  • StripleStrom

    400 is a good displacement. Useable power and torque, but in a light weight package that isn’t intimidating.

  • Craig Hoffman

    This sounds like a potentially awesome playtime track day bike too. Something that can have the snot run out of it and go pretty fast, without being too much of a handful. Just do the usual mods, tires and suspension upgrades, and then,without being too serious about it, go have fun.

    America has historically been a tough market for 400cc sport bikes. Perhaps now is finally their time.

    • Johnny Blue

      Why? By the time you’re finished with the mods and the upgrades you’ve already spent a big chunk of money. For less than that you can get a second hand, low mileage 600cc real sport bike and go to the track without any upgrades. The suspension is already pretty good for track days, not to serious playing and a 600, or 636 Ninja ZX6R is way more fun than these entry level bikes will ever be.

      • Born to Ride

        Not everyone wants to learn how to race on a 100+ hp bike that’ll do a buck forty down the back straight. That’s why the 250, 500, and 650 classes are always packed with club racers who want to have a good time without the added expense and higher risks.

        • Johnny Blue

          From my track experience, people don’t get in trouble on the back straight. They get in trouble in corners. I don’t see how a better handling bike is more trouble in corners.
          And Craig said it would be a “potentially awesome playtime track day bike”. Track days playtime is different than learning to race. As for the expenses, by the time you finished setting up the new Ninja 400 to make it track worthy, you’ve already spent more than buying a used 600cc and doing nothing to it except prepping it to meet your local track’s safety rules. Because the 400 is not even close to the 600 when it comes to braking and handling/suspension. If the engine power is what bothers someone, just put a throttle stop on the 600… until they’re ready for more power.

          • Born to Ride

            Ah, you must be unaware of the the primary expense of racing and track riding in general. Tires my friend, tires. When you go faster and have more horsepower, you burn through tires at a seemingly exponential rate. Guys on 250s sometimes get away with racing a whole season on 2 sets of tires, one set for practice and one set for race days. Talking to friends that have raced in both the 650 and 600 classes, tires last literally twice as long on a 650 twin compared to a supersport. Track days are all about fun, if you have more fun on a lighter bike that you can wring out for all it’s worth, then you’ve accomplished the goal.

          • Johnny Blue

            Having had my own track bike I am very aware of how quickly tires go. I was only talking about the initial investment in buying and setting up the bike. A Ninja 400 is very underwhelming and it will never be as fun as a 600 sportbike. Once, at the end of a track day, I got to try a Kawi 650. After riding all day on a Ninja ZX6R the 650 felt so bad. The suspension was so soft it was almost unrideable. I would never pick a street bike for track riding. Except maybe the KTM 390… 🙂

          • Born to Ride

            And visversa for me. I don’t really get the appeal of riding a bike that was designed for the track on the street. Horses for courses.

          • Johnny Blue

            Well, I totally agree with this guy:
            https://www.youtube.com/watch?v=X0maT3gd8qE
            R1 Sjaak… 🙂

          • Craig Hoffman

            Ah yes, I forgot about the KTM. Seems this niche is already occupied 🙂

          • Johnny Blue

            I tend to like more the tighter tracks with shorter straight lines. Top speed is not much fun for me. I like more the turns and the acceleration/deceleration segments of the track. But any track is better than nothing! 🙂

        • John A. Stockman

          Fun is subjective of course. I started out on a KZ250, rode that thing all over the west and Canada for 2 years and 38,000 miles. Moved up to a KZ440, had 3 in succession and approx. 120,000+ miles between all 3 KZ440s. Right after I got the first ‘440, I found a Yamaha SR500, modded it for club racing. Slim, light weight, huge fun. 2 sets of tires each season. The atmosphere at the races and in the pits was terrific. People helping out, sharing lunch, maybe a few parts here and there. Guys raced old CB Hondas, 2-stroke RZs, so much variety. Add in a few women racing also, it was great. I was mostly a mid-pack runner, but I was there for the fun, and I squeezed so much of that out of those experiences. What’s “right” and fun for me isn’t necessarily the same for someone else, but there’s a lot of choices to fit in with your personal mantra of fun.

          • Born to Ride

            Hell yeah, that’s exactly what I was trying to get across. From what I have heard from guys brave enough to toss their hat in with the Supersport class, you end up with overcrowded paddocks, hardcore squids that take people out with sheer stupidity, and tire bills that approach a couple grand per season. No thanks.

  • hunkyleepickle

    The brief sale of the Ninja 400 in some markets, including up here in Canada, was mostly a failure. Granted that bike was just a sleeved down Ninja 650, with all the extra weight of that already lardy, unexciting bike. A nicely goosed up Ninja 300 up to 400cc could be a very fun little bike. Incidentally, is this mostly a move to make the bike Euro4 compliant? Because that has so far mostly meant a heavily stifled bike that needs the extra displacement just to maintain its already modest power figures.

    • denchung

      This is for Euro 4 but also a matter of keeping up with the competition. This would give Kawasaki the edge in displacement over other manufacturers’ entry level sportbikes.

  • Rob Alexander

    The thing I like about a little bigger bike is they won’t outgrow it as fast and be dying to get a bigger bike…. But it still won’t have the torque hit that a bigger bike has, which IMO is what’s intimidating to beginners (why on earth people start out on Harleys, I’ll never understand)…. I mean there’s nothing a ~400cc bike can’t do pretty comfortably, whereas a Ninja 250 *can* absolutely cruise at 85 on the highway, but it’s turning 10.5K and your airbox will be full of oil if you do that regularly. A 400 should be able to tone down the RPMs a little. Even worse in the cruiser segment, where a 250 can barely do 65 – Honda’s got that covered now with the Rebel 500 though.

    • Gabriel Owens

      Recently rode the rebel 500. Was surprised at how well it handled my 225 pound body although I was cramped. Fun little bike. Not enough oomph for me though.

  • kawatwo

    Can’t wait to see the specs. If they can keep the weight close to the current 300 this should be a blast. Want one!

  • schizuki

    Bump it up to a 500 Ninja next year, give it flourescent pink and teal graphics, and I can re-live the ’80s!

  • Rocky Stonepebble

    I know it’ll never happen, but bring back the Rz350. Best beginner bike ever.

    • spiff

      I think the Duke 390 is my vote for best beginner bike. That is if the options are limited to the street.
      That said, they should get on the direct injection band wagon, and build a new RZ350. Build two. One modern, one retro, just like the Z900.

      • The band wagon with whom, exactly? Bimota? Orbital? Is it 1995 again? Where’s all my hair?

        • spiff

          KTM of course! Oh, it’s happening…I mean it’s coming!

          • What are you buying first? The clean-burning two-stroke 400 sportbike, or the Honda V-5 sportbike for under $10,000?

          • spiff

            Given the choice? I’ll take the V-5 for $9999 Alex.

      • Rocky Stonepebble

        Why two? I still have a 1990. Build those. Great beginner bike, and still good for us aging hoons.

        (I’ve owned 5 Rz’s, 2 RD’s a Rz500, RG500 and an NS400R. Plus others)

        • spiff

          Which one would be your choice for a 100 mile Sunday ride? I always thought the RZ500 was cool.

          • Rocky Stonepebble

            Any one of them. I toured for weeks long holidays on all of them. Would lash on the camping gear and a bag of clothes, and go. They were all fun.

          • spiff

            Very cool my friend.

          • Rocky Stonepebble

            The RG500 Gamma had the best handling. The Rz350’s were just great all-round bikes.

          • Kenneth

            I toured cross-country on a CB350 in ’71 (with a large backpack lashed to a sissy bar). But you can take a lot more punishment when you’re 19.

      • Kenneth

        So riders can deal with the same problem of intake valve deposits as found in d.i. car engines? Some innovations arise primarily to help manufacturers meet increasingly stringent fuel economy standards, leaving owners to deal with the increased maintenance hassles and costs.

  • Barry_Allen

    With MotoAmerica replacing the KTM RC Cup with the Junior Cup for 2018 we might see a few of these on the track alongside the KTM 390’s

  • Matt Howerton

    Would be really cool if it were an inline 3cyl. Might spark a fun multi cylinder war with the manufactures in the small displacement bikes.

    • Kenneth

      Kawasaki certainly has experience with triples (how about a new “Mach III”?).

      • Matt Howerton

        Yeah but all were two strokes if I’m remembering right. But, they certainly have the money and facilities to come up with something new. Most likely will be a twin though and I was just throwing that there. More like wishful thinking.

  • Bmwclay

    I would like to see a nice 400cc 2-stroke Kawasaki 4 cylinder. You know they can do it. With all the new technology it could easily pass CARB. Think of it, 5 ft-lb torque at 16000 rpm. Perfect starter bike.

    • Or they could partner with Liquid Moly and make a 4-stroke 400 that would get 100 mpg and never need an oil change, too!

    • Rocky Stonepebble

      Too many cylinders. You had me at “400cc 2-stroke.”

  • falcn

    Uh oh. Is Kawasaki about to offer us the holy Grail mini adv bike Versys 400!? I hope so! I’d prefer a little naked 400 Z in addition to the Ninja myself.

    • pidginTM

      Naked 400 would be amazing

  • pidginTM

    Now slap this engine on a motard (like dorsoduro/hypermotard) or a sexy naked bike.

    • spiff

      That’s a good idea.

  • kenneth_moore

    I wish Kawi or Honda would offer one of their <500 cc inline fours in the US. Twins are ok, but they'll never match the feeling of a small displacement four winding out the gears.