There’s a reason small-displacement sport and naked bikes keep showing up, no matter how obsessed the industry gets with bigger engines and bigger numbers. This segment has always been the gateway. It’s where riders learn throttle control, braking feel, and how to actually carry speed instead of just blasting past it. And for a lot of people, it never stops being fun.
Light weight, usable power, and engines you can wring out without doing triple-digit miles per hour tend to age really well.
Back in the late ’80s and early ’90s, that formula hit a sweet spot with inline-four 400cc machines. Bikes like the CB400 Super Four weren’t about outright speed. They were about smoothness, high-revving character, and precision. You got an engine that loved to spin past 12,000 rpm, paired with a chassis that actually let you use all of it. That combination built a cult following that never really went away, even after emissions rules and market shifts pushed those bikes out.
That’s what makes this latest move from Honda interesting. While most of the world has settled into parallel twins in this segment, Honda is bringing the small-capacity inline-four back into the conversation.
The new CB400 Super Four E-Clutch Concept and CBR400R Four E-Clutch Concept pick up right where the old formula left off, at least visually. The naked bike leans into that timeless round headlight, exposed frame, and clean proportions. The sportbike goes the other way with sharp bodywork and a layout that clearly takes cues from the CBR family.
But the real story isn’t the styling. It’s what’s happening underneath.
Honda hasn’t released official horsepower or torque figures yet, but the bigger takeaway is the tech. Both bikes are built around a modern inline-four engine paired with throttle-by-wire and Honda’s E-Clutch system. If you haven’t been paying attention, E-Clutch basically lets you take off and shift without manually operating the clutch, while still keeping the feel of a traditional gearbox. You can ride it like a regular manual, or let the system handle the clutch work when you don’t feel like it. Think of it as the best of both worlds.
That might sound like a small thing, but it changes how approachable these bikes are. Inline-fours have always had a reputation for being a bit intimidating, mostly because of how they build power higher up the rev range. Pair that with a clutch-heavy riding experience in traffic, and you can see why a lot of newer riders gravitated toward twins instead.
This setup flips that script. You still get the smoothness and top-end rush of a four-cylinder, but with a layer of convenience that lowers the barrier to entry. It’s less about dumbing the bike down and more about letting more riders actually enjoy what makes these engines special.
There’s also a bigger picture here. For years, the middleweight space has been dominated by cost-efficient parallel twins. They’re easier to build, easier to package, and easier to tune for everyday riding. That’s why you see them everywhere from entry-level naked bikes to off-road ready adventure machines.
Honda bringing back a 400cc inline-four, even as a concept, signals that there’s still room for character in this segment. Not everything has to be about hitting a price point or flexing the best specs. Sometimes it’s about how a bike feels when you wind it out, how it sounds at high rpm, and how it connects with the rider.
Of course, the big question here is whether these bikes stay limited to Asia or eventually make their way to other markets. But even as a preview, they’re doing something important. They’re reminding everyone that small bikes don’t have to be boring, and that innovation in this space doesn’t always mean going electric or adding more power.
Sources: Le Repaire Des Motards, Cycle World
