Sportsbikes gıve you wings… "The biggest untapped area is active aerodynamics’
… well, they soon will. Ben Purvis explains why we should all be getting excited about aero…
Aerodynamics have been a backwater of motorcycle design for decades. Compare a Yamaha M1 Motogp bike from 2004 with one from 2014 and you’ll struggle to spot any significant changes in the shape. But in 2015 a revolution started in Motogp as bikes began to sprout wings and now, following the inevitable delay between prototype and production, the same transformation is coming to showrooms.
What’s more, these changes will be more pronounced than anything we’ve seen so far in racing because road bikes aren’t shackled by race regulations. Although a handful of production bikes already sport winglets – the Kawasaki H2R and Ducati Panigale V4R – 2020 sees them move into the mainstream. Honda’s new Fireblade, Ducati’s reworked Panigale V4 and new Streetfighter V4, MV Agusta’s Brutale 1000 and Aprilia’s RSV4 1100 Factory have all grown wings.
Do they actually work? When it comes to racing, yes, otherwise they’d be instantly ditched. But rules now limit what Motogp designers can do with wings, so their effects are small – important, but minimal. Road bikes, however, have no such restrictions so their wings could be far more effective. But they’re not there yet. Ducati say the winglets on the 2020 Panigale V4 create 37kg of downforce. Sounds good, but you have to do 186mph to achieve nd it, and since aerodynamic forces are proportional to the square of velocity, downforce plummets as speed drops. According to Ducati’s figures, at 60mph there’s just 4kg of downforce and at 30mph the wings generate only 1kg. It’s early days though. The biggest untapped area is active aerodynamics, where wings can move to change downforce depending on your speed and lean angle. The potential is huge because bikes aren’t stable aerodynamic platforms like cars. Lean far enough over in a corner and the previously-helpful downward force from a wing will push the nose away from the apex. The drag of winglets also reduces top speed, so ideally you’d get rid of them when you’re flat-out Mo to gas as well. regulations stop mo tog pas well. Regulations stop Motogp bikes using this tech but there’s no such rule in World
Superbikes. In fact a rule clarification for 2020 says: ‘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.’
That means any manufacturer wanting to explore the potential of moving wings in racing needs to offer them on a production road bike. Honda recently filed four separate patent applications for moving superbike aero. Two illustrate winglets that retract into the bodywork when they’re not needed. The author of the first, Takuya Yamasaki says: ‘It is possible to obtain downforce by moving the wings to the operating position. By moving the wings to the storage position, it is possible to reduce the air resistance.’ An IMU controls the whole process, deciding when the wings need to be extended or retracted. Another Honda patent suggests a nose that hinges like Concorde’s, disrupting the airflow and killing the downforce in corners. Its inventors, Hisafumi Matsuo and Takeshi Kimijima, explain: ‘The tip portion swings downward… and the flow of the running wind along the upper surface is disturbed. As a result, the downforce effect is reduced, so that the motorcycle can be easily banked and turning performance is improved.’ The fourth idea, from the same engineers, is even stranger. It features vibrating body panels to detach the airflow and reduce downforce, making cornering easier. If just one of these ideas works it’s likely to be adopted onto a road bike used to homologate future WSB racers, forcing other manufacturers to react. Aprilia are already working on an active aerodynamic system, although they’re keeping schtum on the details, and you can be sure every other manufacturer in superbike racing will be preparing to react.