Sykes, who had two small crashes today, was second fastest and he again used only a race tyre.

Both KRT riders used two bikes each to make comparisons in set-up – as did some of their official team rivals. Tom best time was 0.477 seconds behind his team-mate at the hilly Portimao circuit, which was the scene of a practice crash that stopped Sykes racing here in 2017.

Michael van der Mark (Pata Yamaha WorldSBK) also set laps on two machines, going third fastest overall. Still working to overcome stability and throttle response issues, Marco Melandri (Aruba.it Racing Ducati) placed fourth best, with British runner Alex Lowes (Pata Yamaha) fifth.

The continuing improvement in the Red Bull Honda camp allowed Leon Camier to post sixth best WorldSBK time, a 1’42.944. He continued to use the existing Cosworth electronics system today, rather than try out the intended new Magneti Marelli components.

Camier was followed in the rankings by Eugene Laverty (Milwaukee Aprilia) with a 1’42.953, with Chaz Davies (Aruba.it Racing Ducati) just behind him, completing the top eight competitors.

Right in the mix with the leading riders, Turkish rookie rider Toprak Razgatlioglu (Kawasaki Puccetti Racing) was close behind Davies. His recent Superstock class rival Michael Ruben Rinaldi, who will be the third rider in the Aruba.it team at European races in 2018, was one place behind, but also one place ahead of regular Superbike rider Xavi Fores and his Barni Racing Panigale.

Loris Baz (Gulf Althea Racing BMW) was 12th overall, and lone MV Agusta rider Jordi Torres 13th. Lorenzo Savadori (Milwaukee Aprilia) had his bike stop out on track and he was 14th overall. America’s Jake Gagne, loving his first experience of Portimao, registered a 1’44.052 on his Red Bull Honda, before his bike hit engine problems and his day came to a premature end, in 15th place.

He will take to the track again on Monday, with his compatriot PJ Jacobsen (Triple M Honda) who set a 1’46.839 on his first day in full-on WorldSBK testing.

Top WorldSSP rider was Raffaele De Rosa (MV Agusta Reparto Corse by Vamag), next best being five times champion Kenan Sofuoglu (Kawasaki Puccetti Racing).