Milwaukee NBC affiliate, WTMJ-TV, may have just spoiled Kawasaki‘s surprise for the 2018 model year by filming what appears to be a restyled Ninja 400. The previous generation 400, although not available in the U.S., was a downsized Ninja 650 and styled in the same vein with an under-engine exhaust. The higher-mounted muffler and swoopier bodywork seen here points to this being a stylistically revised model, though the narrowness of the bikes hints at the continued use of a parallel-Twin engine.

Any further comments on internal changes would be pure conjecture, but we’re not gonna let that stop us. We surmise that the 400 has undergone a Ninja 300-ification. The wheels look similar to the 300. The muffler and swingarm look virtually identical – which also means the shock has been relocated from the 650’s side-mount placement. The bodywork that we can see looks likes a brawnier version of the Ninja 300, and perhaps this new 400 has a larger tank. We expect the wheelbase to remain essentially the same since the 300 is only 0.2 in. shorter than the current 400’s 55.5 in. Engine internals are likely to be updated, but we’d expect the bore and stroke to remain close to its current 58.4 mm x 54.3 mm along with a 11:1 compression ratio.

The filming of the commercial in an American city also means – we hope – that the sporty 400 will be headed Stateside.

2018 Kawasaki Ninja 400

Why do we suspect that this bike is the 2018 Kawasaki Ninja 400? We will never reveal our sources.

To see the full video report, go to the WTMJ-TV website.

The 2017 Ninja 400 available in Japan bears more of a resemblance to the Ninja 650 than to the bigger ZXs. The bikes shown in Milwaukee, look much more in line with Kawasaki's current styling.

The 2017 Ninja 400 available in Japan bears more of a resemblance to the Ninja 650 than to the bigger ZXs. The bikes shown in Milwaukee, look much more in line with Kawasaki’s current styling.

  • Old MOron

    I’ve been out of club racing for a long time, but can envision a class where the Ninja 400 and the RC 390 go head-to-head. Wouldn’t that be fun?!

    • Jason

      Not for the RC390. Single vs. Twin

      • Old MOron

        I thought about that, but KTM seems to make magic singles that behave like twins. Oh well, maybe you’re right.

      • Sayyed Bashir

        The RC390 will win.

  • kawatwo

    If they could make a 400 and keep the weight about the same as the current 300 that would be amazing. Bring it on!

    • Kevin Duke

      That can’t happen if the motor is based on the 650…

      • Campisi

        The underlying hope is that we’re looking at a Hot Rod Ninja 300, rather than a Sixty2’ed Ninja 650. Considering that the latter is a regulatory special that wouldn’t make sense for the U.S. market, I like to think that the more exciting former option is also the more likely one.

        • kawatwo

          Exactly, Hopefully it is a bored out 300 (can they stretch it that far 🙂 with the same chassis which will hopefully keep it under 400 pounds gassed up. We shall see. If it is just a sleeved down 650 then they might as well keep it over seas.

          • Jason

            Considering the 300 is already a sleeved up 250 I doubt it has room to go to 400. If 400cc was possible I suspect they would have done it for the North American market from the start.

          • Kevin Duke

            Yep, I feel the same way.

          • Jason

            With a little more thought, I don’t see why Kawasaki couldn’t change the cylinder block and add more stroke to get to get 400cc from the 250 engine.

            However, I still think if Kawasaki was going to make a 400cc version of the Ninja 250 engine they would have done it already when the Ninja 300 and Versys 300X were originally released.

          • GregS

            That would mean adding another 2/3rd of an inch to the stroke. Not sure the crankcase could handle that.

  • Starmag

    The east side of M’waukee is loaded with the cheesy “rebel” skinny jeans and old golf hat uniform crowd, I wouldn’t think that was the little Ninja’s market.

  • toomanycrayons

    Is “accidental advertising” a thing? To #fake quote Kellyanne: “It is, now.”

  • KPC

    In a perfect world, this engine would be based on the Ninja 300, Kawasaki then would have put the bike through the same weight reduction program the z650/900 went through and drop say 35-40 pounds. Then we would have a 350 pound (wet), 50 rwhp little screemer. There is a market for a bike like this in the US. Screw all these A2 license compliant euro bikes. But I fear this will be a 400 pound steaming pile of “just mailed it in” engineering.

  • Jason M.

    I’m not sure I’m down with this. OEM’s keep upping the displacement until we’re back to 600’s are back to becoming the “beginner bike” again.

  • Michael Paul

    What they needed to do was take this back in time with a high reving four cylinder. A bike people can get excited about and ride the piss out of. I would pick one up in a heartbeat. A 400 parallel twin puts me to sleep.

    • larry warhurst

      Me also, i have more interest in a 450cc super moto. I don’t know if a starter could be added cost effectivly to the KX450. The Suzuki Super moto is the only cost option, the others are TOOOO expensive. Just a simple 1-lung street hooligan.

  • Rahul Nair

    Is it only me or did anyone else read that name plate as a “420” or maybe a “430”?

    • KPC

      I see it too. Honda has 300 and 500cc bikes why not Kawasaki??

    • jeffbricks

      Looking closer I now see what you are saying. It does look a bit like 420. If so it would probably develop a bit of a cult following in the US almost immediately. They could do a promotion to sell it with a tank bag to hold snacks.

      • Brett Lewis

        Insurance rates might be higher on that model.

  • Sayyed Bashir

    Why does Kawasaki have to go to Milwaukee to shoot a Ninja 400?

    • Colonel Matumbo

      Because it’s against The Law to Shoot Ninja’s in California !
      Thanks for all the standup type comedy you post.
      Congrats S-Bash, You are a credit to your Gender.

      • Sayyed Bashir

        Well what are they trying to prove? That it is “cool” to shoot in the shadow of the great Harley Davidson? That it isn’t a motorcycle unless it is shot in Milwaukee? If it was a cruiser, I understand they would want to shoot in front of grungy dilapidated buildings like all cruiser wannabes do, but a 400cc Ninja? They should have shot it in a children’s playground.

        • Colonel Matumbo

          No shooting in Children’s Playground!
          It’s not nice.

  • Frank Radaj

    My guess is this is the replacement for the Ninja 300. Should weigh the same with close to 50hp. I like the current bike so I hope they haven’t ruined it. Should be quicker than the RC 390. Maybe we will also see a new R4.

    • Sayyed Bashir

      Why would it be quicker than the RC 390?

      • KPC

        The 2018 390 just got heavier and slower to meet A2 licensing requirements in the EU without needed to be restricted like they used to be. If the 400 is a non-A2 bike, it would eat today’s 390 alive in a straight line. If its also A2 compliant, then who cares, they’re both boring beginner/commuter bikes.

  • spiff

    You shouldn’t have told us about the commercial. Just let us know it’s coming. In time the naysayers will be silenced, and the sherlick status will grow. Same how you told us about the new Ducati engine. Let us marvel at your insight into the future. Be the man behind the curtain. 🙂

  • sgray44444

    I think it is laughable how the manufacturers pressed the displacement reset button, and starting with 250cc bikes, we are watching as every year they “one-up” each other with a new model that is slightly larger than the previous year… 250… 300… 400… Man, could you imagine a 4 cylinder 600! That would just be crazy! Are we really that stupid?