The Winglet Loophole: Ban Allows Unlimited Development Of Internal Wings

Winglets may have been banned for 2017, but the drive for aerodynamics development continues. This time, however, winglet development will continue on the inside of the fairing, rather than the outside. The development ban applies solely to the exterior surface of the fairing, and not the interior. 

What this means in practice is that while the shape of the fairing must be homologated at Qatar, with one update allowed during the season, that only applies to the outer surface of the ducts, and not to the vanes (the small struts or winglets inside the ducts which control the airflow and can be used to alter downforce) inside those ducts. Development of aerodynamic control surfaces will still be allowed, as long as the changes remain on the inside of the fairing.

An eagle-eyed reader spotted the gap in the regulations. Section of the FIM Grand Prix Regulations reads as follows:

Only the external shape, excluding the windscreen, is defined in this regulation, so the following parts are not considered as part of the Aero Body: windscreen, cooling ducts, fairing supports, and any other parts inside the external profile of the bodywork.

When reached for comment by email, MotoGP Technical Director Danny Aldridge responded "You are correct in the fact that I only control the external shape/profile of the fairing. Meaning, Yamaha can in theory change or adjust their inner supports as often as they wish. When the regulations were being discussed with the MSMA, this was one of the criteria that they requested in the wording of the regulations."

The shape of Yamaha's new fairing helped to give the game away. As you can see in the photo by Andrew Gosling below, Yamaha's fairing consists of an outer duct fitted to the exterior of the fairing, with two supports or vanes on the inside. Yamaha can alter the position, size, and shape of those supports to suit the characteristics of each different track, or as they learn more about the performance of their ducted vane fairing.

On Thursday, Suzuki and Aprilia also rolled out their new aerodynamic fairings. Both took a different approach to creating downforce and aerodynamic surfaces to Yamaha, as you can see in the photos shared on Twitter by WorldSBK commentator and Paddock Pass Podcast regular Steve English.

The solution selected by Suzuki most closely resembles the Yamaha design, though its placement is very different. Where Yamaha chose to put its duct on the upper part of the mid fairing, Suzuki have added it on the side of the nose. Clearly visible in English' excellent picture is the central strut or vane which will provide downforce. Suzuki are free to modify this vane as much as they like.

Aprilia's solution is very different, consisting of an open aerodynamic duct either side of the nose. Downforce in this design is generated by the shape of the inner channel, and the shape of the outer duct. There does not seem to be as much room for internal modification of the duct as on the Suzuki or Yamaha. 

Aprilia's design may also spark debate over what constitutes the outer surface of the fairing. The wording of the rules is ambiguous, though an initial reading of the rules suggests that the inner surface fo the duct is not considered to be a part of the "external profile" of the fairing.

The wording of the new regulations also makes clear that the ban on winglets was only introduced on the grounds of safety. And in a sense, the rule makers were bound by this, as the Grand Prix Commission only has the right to ban a technology on safety grounds, if the manufacturers in the MSMA want to allow it.

By having enclosed, smooth surfaces on the outside of the new aerodynamic fairings, the manufacturers are complying with the rules on safety grounds, while continuing their development of aerodynamic fairings and exploring the effect of downforce on motorcycle dynamics. Though many senior officials inside Dorna feared the cost explosion which will likely ensue from allowing aerodynamics, the genie is out of the bottle, and they have no grounds to ban it.

With Yamaha, Aprilia and Suzuki having unveiled their aerodynamic solutions, we now await what Ducati, Honda and KTM will do. Ducati have already hinted that they are keeping their aerodynamics under wraps until Qatar - either the test, or a private test before the race. Honda remain evasive, but are likely to also have some form of aerodynamic assistance before the start of the season. Only KTM have shown no interesting in developing aerodynamics so far. But as this is their first year in MotoGP, the Austrian factory already have a massive list of areas they need to work in.

The good news for riders of road motorcycles is that the designs being tested in MotoGP are far more likely to make it onto road bikes than the previous generations of winglets. Getting type approval for motorcycle fairings with internal aerodynamic devices is far easier than for fairings with external wings attached. How quickly this technology actually trickles down to street bikes remains to be seen.


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I guess a good question would be, why would this technology trickle down to street bikes? OK maybe on sport bikes that are realistically going to end up on the track, but beyond that I don't see the point for the street.

Something else that never made sense to me about the winglets is, wheelies are a bigger problem in lower gears, where you have the most torque trying to lift the front end.  Once you get into higher gears it's less of a problem (OK maybe still a problem on MotoGP bikes).  In contrast, the force pushing down the front of the bike to prevent wheelies is more the faster the bike is going, so the effect is least when it is needed most, at lower speed lower gears....maybe electronics for lower gears, winglets for higher gears? Only way it makes sense to me...

It's reason enough for something to turn up on road bikes; actually doing something useful is irrelevant

As for why they're effective, it's because a GP bike is powerful enough to want to backflip even at the sorts of speeds where downforce generating aerodynamics become effective.

Good on ya Kenup!


I'd end with HUG like I do w all my friends, but this is still motorcycle racing right?
Thanks for all the great pictures, and David you are journo GOAT.

Good to be alive mates, THIS SEASON - IT IS A GEM!

The design brief for a MotoGP motorcycle is quite different to a street bike's brief. The need to stabilize a racer braking from 215 mph or accelerating with 240+ hp isn't really a compelling concern in the marketplace today. Of course the "cool" factor is a proven money-maker for manufacturers pedelling race replicas to poseuers and folks with silly amounts of wealth, but that market is "small." Remember that downforce equals drag equals decreased mileage. This is a real concern in the world today and going forward.

doesn't seem that long ago when any auto pretending to be 'sporty' had to have a spoiler at the back.  logic doesn't apply.

David, seems all the current vanes are passive.  Do the regs ban the vanes from changing their angle of attack via servos?   or are they doing that already?


Agree! Surely having variable angles would be particularly useful. You wouldn't need or want the down force all the time and being able to match the down force to parts of the circuit / time where it's most needed would be the ultimate.

I don't  follow or display any interest in F1 however a I vaguely remember a "minor controversy" involving Ferrari? where the shape of the external ducts(wings) changed due to the forces from wind pressure. At the elite level of anything especially where money or prestige is involved there are a lot of clever minds thinking about what does the rule allow me to do. What opportunities does that rule provide me with?. What does static mean anyhow?

... what about moving parts for "cooling"?


If these vanes are internal, how are they technically defined as different from things like variable inlets (i did hear honda is doing downforce stuff with their air intake?) or exhaust valves?

Yes, i know... its clear what the manufacturers are doing with them, but unless it is clearly defined in the rule book as to what consititutes an aerodynamic device you just know they're going to be pushing the boundaries.




also, surprised no one is trying things like blown diffusers (from F1) with the exhaust yet.  not sure how much thrust/downforce you could get with a MotoGP exhaust, but surely if they were to angle the pipe downwards on the tail of the bike it would help push the nose down with the exhaust gas.

... how is "internal" defined?

is there a minimum covering required?

i.e., how long does the tunnel have to be?

if i cover a wing with an outer rim that extends backwards say, 2-3 cm with the fairing, is that enough?  what about 10 cm?  20?



I suspect we'll see a lot of rule book updates in the next few years :)

Thanks, David, that's what I thought.  But your statement that the Grand Prix Commission could only ban a technology on grounds of safety if the MSMA wants to use it perked the question.  Could the logic of moving vanes push the issue? Cuz I don't see a safety rationale for that ban...  or is it more like the ban on ceramic brakes?

It's been banned for as long as I have been covering the sport. I suspect it has been banned for a very long time. The MSMA would have to propose it. I don't think there is much desire in the MSMA to get into moving aero parts though, at least not at the moment. Four, five years down the line, and things could be different. 

The external winglets were banned due to rider's concerns about being cut up by them. The rules were written so that would not be a problem, whilst still allowing manufacturers to use aero for wheelie control in a safe way. It's hardly a loophole. If they had wanted to completely ban aero for wheelie control they would have written the rules appropriately.

WTF have they done??? These solutions(besides Yamaha) look like piss. They take great looking bikes and then them into F'ing puffer fish. SMH. 

Ducati have already patented a variable outlet exhaust and are using it, as one can see in the pictures from the PI test. That little box underneath the pipe, beside the salad box, houses the motor that opens and closes it.

I think the question is not whether streetbikes will follow this trend. It is the oppposite, these airducts are common on street bikes and are just old becoming kind of old fashioned when minimalism became hot. See here a perfect example of the much spoken "revolutionary" Yamaha technology: kawasaki z1000sx