Active Aerodynamics: The Future For Superbikes

Rule-makers okay moving bodywork for WorldSBK, with big implications for streetbikes.

Honda patent
Honda has filed more patents involving active aerodynamic systems that include a folding fairing, moving winglets, and vibrating bodywork.Honda Patents

It’s fair to say that the development of road-going superbikes during the 2010s was dominated by lightning-fast advances in electronic rider aids, bringing invisible but significant improvements. But in the 2020s we can expect some much more overt changes to the superbike picture as active aerodynamics become the new field of competition.

Two sentences in the 2020 WorldSBK race regulations draw up the battle lines. Appearing in an FIM rule clarification published on November 28, they read:

“For active or dynamic aerodynamic parts _only_ the standard homologated mechanism may be used. The range of movement must be the same as that used by the homologated road machine in normal use—not the mechanical maximum.”

“Active or dynamic aerodynamic parts” means moving bodywork, something that’s long been banned in MotoGP and hence remains an unexplored field—but it’s a fertile one that bike designers are already starting to plough.

Back in September, before the 2020 Honda CBR1000RR-R Fireblade was unveiled, we revealed that Honda was developing a mechanism that would enable winglets to be retracted into the bike’s side panels when the downforce they created wasn’t needed. That mechanism hasn’t emerged yet on the production CBR, but it’s clear that it wouldn’t take a huge update to include it in future derivatives.

Wings patent drawing
Previous patent drawings show wings that retract and extend from the fairing depending on the speed and lean angle of the motorcycle.Honda Patents

Similarly, Aprilia’s 2018 RS660 concept bike promised active aerodynamics. The 2020 production model doesn’t use the system, but it’s clearly something the firm’s designers are working on. And with the official go-ahead from the FIM to allow the use of active aerodynamics on future WorldSBK bikes, provided the road-going version has the same equipment, every manufacturer taking part in that series is sure to be exploring how to implement such a system.

Three New Honda Active Aero Ideas

1. Winglets

Honda is clearly hitting the ground running, as within days of the FIM ruling three new patent applications were published in Japan revealing how active aerodynamics could be applied to a future superbike.

The first isn’t dissimilar to the patent we saw back in September, revolving around the idea of retractable, side-mounted winglets. Where September’s patent featured biplane-style winglets inside an outer cowling—very similar to the fixed winglets on the real 2020 CBR1000RR-R—the newer one shows larger, single-layer wings fitted much lower on the fairing sides.

Honda’s patent explains that the wings are useful at certain times, keeping the nose down under hard acceleration, for instance, but have a downside when it comes to out-and-out top speed. Wings bring drag which can reduce the bike’s flat-out potential, so Honda’s patent adds pivots at the front of the wings, so they can be mechanically retracted either at the touch of a button or automatically when the bike passes a certain speed, reducing drag.

winglet patent
The latest moving winglet patent from Honda shows larger units (#80) placed low on the fairing.Honda Patents

In corners, the wings can also cause problems. When a bike is banked over the downward force they bring turns into a largely sideways force, trying to push the bike’s front wheel away from the apex. Therefore Honda floats the possibility that the wings could also be withdrawn automatically in corners by measuring bank angle.

2. A “broken” nose

Winglets aren’t the only part of a bike that creates a downward force, and Honda’s second new patent application looks at another source: the nose.

The sloping front end and windscreen of every modern superbike creates at least a bit of downward aerodynamic pressure, pushing the front wheel toward the ground, and Honda reckons there are times when it’s not helpful.

airflow patent
By folding the nose into a vertical position (#80), Honda aims to disrupt the airflow over the front of the motorcycle, thereby reducing downforce when cornering.Honda Patents

In particular the firm believes that when a bike is cornering, the downforce introduced by the nose profile will tend to push the front wheel away from the corner. Its solution is a movable nose tip. The idea is that in corners, the tip of the bike’s nose hinges down, operated by a servo. In doing so it presents a vertical face to the oncoming air, creating turbulence that detaches the airflow from the rest of the bike’s front end and windscreen to eliminate the downforce they create. In the words of Honda’s own engineers: “As a result, the downforce effect is reduced, so that the motorcycle can be easily banked, and turning performance is improved.”

movable nose
Honda’s movable nose (#80) in the high-speed position.Honda Patents

The idea is to use an IMU to judge whether the bike is cornering or not and to automatically move the nose tip depending on the instructions it sends. As soon as you’re upright and accelerating again, the nose slots back into its normal position to bring the downforce back and reduce drag.

3. Vibrating bodywork

Perhaps the most unusual of Honda’s new active-aero ideas is one that won’t visibly change the look or shape of the bike at all. Instead the idea is to vibrate key parts of the bodywork at specific frequencies to detach laminar airflow at specific moments.

Like the “broken nose” idea above, the main purpose of the idea is to damp the aerodynamic force that’s created by the bike’s sloping nose and screen when the bike is leaning in a corner.

Rather than visibly moving the panel, the idea is to put at least three “vibration generators” underneath the nose bodywork. These are simply small electric motors that spin an unbalanced mass; the same idea is used for haptic feedback in cellphones or for the “rumble” effect in game console controllers. By tailoring the mass and the speed of the motor, the frequency and amplitude of the bodywork vibration can be adjusted, and when it’s done right, the result is to detach the airflow over the nose, reducing the downforce it creates and helping the bike turn.

Vibration generators
Vibration generators could be another viable way to disrupt airflow for desired handling effects. The generators (labeled 71A, B, and C) are placed beneath the bodywork.Honda Patents

Honda also presents the idea of fitting similar vibration generators into the bike’s side panels. Here, the result of detaching the airflow is to reduce the bike’s straight-line stability, making initial turn-in easier.

As with the other active aero ideas, Honda’s patent suggests the vibration generators would be automatically activated or deactivated depending on speed or the bike’s lean angle, as judged by an inertial measurement unit, so the rider doesn’t need to manually activate them.

bodywork vibration generators
Honda’s bodywork vibration generators spin an unbalanced mass that in turn creates vibrations that is transferred to the bodywork.Honda Patents

What does all this mean? Of course, we can’t know which of the active aerodynamic ideas that are under development will actually make the leap from the drawing board to the production line, but it’s very clear that Honda is serious about developing active aero. The FIM’s recent regulation clarification isn’t likely to be a coincidence either; it suggests at least one manufacturer taking part in WorldSBK has specifically asked about the legality of active aerodynamics before investing further in the idea.

By specifying that any active aero used on WorldSBK racebikes must be the same as the system used on the road-going homologation models, the FIM has ensured that whatever developments arise, real-world riders will be able to benefit from them just as much as racers. It will be fascinating to see what other ideas emerge over the coming months and years as other manufacturers jump on the active aero bandwagon.