Rear wheel cover on the GP19 and carbon swingarm.
David Emmett: The full set of rear aerodynamics on the Ducati Desmosedici GP19, from the swingarm spoiler to the rear wheel covers. The rear wheel cover mounting points are clearly visible: at the rear of the chain tensioner, and at the front below the aluminum bracket with holes. The rear swingarm spoiler caused huge controversy at the start of the year, and now all manufacturers bar KTM have one.
Ducati used a loophole in the regulations to use the swingarm spoiler and wheel covers, but this loophole will be closed for 2020. For next season, all parts which are not part of the structural part of the motorcycle will be classified as part of the aero body, and so their designs will have to be homologated, with one update allowed during the season. So Ducati can start the season with one spoiler, and alter it once during the year.
Lighter front mudguard on the KTM RC16.
Peter Bom: Although it is a little bit difficult to see in this photo, the mudguard ends immediately after the double L of Bull. This leaves more of the front tire exposed, helping it to run a little cooler and prevent overheating. Some KTM riders have complained of this previously.