The New Age of the V4 Road Bike

The holy engine configuration is coming soon to a road near you.

Ducati Panigale V4
Ducati

How often have you, a mere road-pounding mortal, dreamed of walking into a dealership and riding out on a V4 superbike in all its glory? Unless you're hiding a time machine in your basement and can hop back to the early 1990s, you've had very little choice. Back then V4s were all the rage, but they swiftly vanished.

The inline-four has always dominated the mid- to high-end of the sport bike market, but while the I4 re-took the road bike mantle, manufacturers honed their expertise on V4 racing motorcycles throughout the 2000s. Now that racing bikes have used the V4 to recent success, top bike makers are starting to give the engine configuration serious attention. The big brands are scrambling to design V4 liter bikes—sport bikes with 1000cc engines, or thereabouts—and making major noise about the V4’s triumphant return to public roads.

Gianluca Zattoni, Ducati’s head of engine project management, says the manufacturer sees the 90-degree V4 layout as the “pinnacle” of motorcycle engine sports performance. “Compared to a classic inline four,” he says, “the lateral compactness of the V arrangement allows for better mass centralization and reduces the bike’s frontal cross-section.”

Ducati Panigale V4
Four elliptical throttle bodies, each equivalent to a 52mm circular throttle body, gulp in air to help the Panigale V4 make from 214 horsepower on the base model to 234 horsepower on the V4 R.
Ducati

All other things equal, Zattoni says the V4 bike will be lighter and faster when changing direction. That’s why it’s been a no-brainer for racing bikes for a while.

Look around the highest levels of motorsport today, and you’ll see most competition liter bikes buzzing around the tracks with V4 engines. Honda has campaigned the V4-powered RC213V racing-only bike in MotoGP since 2012; Ducati has run the Desmosedici MotoGP machine in various forms since 2003; Aprilia returned to MotoGP in 2015 with the RS-GP; and KTM began the RC16’s MotoGP career in 2016. Road-going bikes, meanwhile, have largely organized their cylinders in every other way except for V4.

“A V4 engine provides many benefits for racing, such as position of the engine, width, and balance, but when it comes to production motorcycles, it becomes more complex, and the manufacturing and customer costs increase,” says Colin Miller. Now a press officer, Miller had worked in the service technical department for American Honda. The automaker sold its first V4 road bike in 1982, and its V4-powered road sport bikes enjoyed glory days throughout the ‘80s and ‘90s.

Ducati Panigale V4
Ducati

But by the turn of the century, Honda’s sport bikes were again powered by inline-fours, and the V4s were stuck unsuccessfully in adventure touring bikes before being pulled from the market altogether. Aprilia was the odd one out for many years. In 2009, it debuted the street-going RSV4, and it’s been the main option for V4-hungry buyers ever since. Ducati offered the Desmosedici RR, a road-legalized version of its MotoGP machine, in 2007 and 2008, but as a $72,000 limited-production bike.

It was only recently that people began talking about a resurgence in V4 road bikes. Now we could be bracing for a downright renaissance.

Ducati Panigale V4
An electric motor slides an upper funnel along steel guides to adjust the length between it and a fixed lower funnel based on the moment's power demands. This variable intake system broadens the power band so that more power is available from low RPM to high RPM.
Ducati

A few months ago, the relaunched brand Norton designed its first-ever V4 and introduced it in the V4 RR. Of course we’ve all heard the rumors that Honda is putting a V4 in the upcoming RVF1000 road bike. (Miller says he can’t comment on future products.) And while Ducati’s signature V2 isn’t going anywhere, the maker’s Panigale V4—launched in 2018 as part of its regular production line—is nudging it aside on the brand’s biggest, fastest bikes. With the same displacement, Zattoni says, a V4 can rev higher than a V2 and squirt out more horsepower, and its shorter crankshaft reduces the gyroscopic effect of engine vibrations affecting the bike’s balance.

V4s are exciting first because they’re novel—or at least, it’s been awhile since so much of the market was building them—and also because they’re pushing bikes into silly fast performance numbers. The natural question many ask, then: When will there be a trickle down to lesser bikes? Not anytime soon.

It’s more complicated and expensive to build a V4 than a V2, I3, or I4, and so the configuration is still stuck on the high end of the market—for now. Zattoni says smaller-displacement sport bikes are now even more niche than bigger ones, so you shouldn’t expect to see V4s in entry-level bikes or middleweights any time soon.

“The sports bike market is reducing year by year, becoming a proper niche,” says Zattoni. “That’s why the manufacturers are building more and more race-oriented bikes, and probably why other manufacturers are building V4 engines now.”

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