Leon Haslam emerged on top of the times at Valencia as four World Superbike teams hit the track for the opening day of a two-day test session.
The Briton posted a quickest time of 1min 34.5secs aboard his Alstare Suzuki to lead the way from Aprilia's Max Biaggi
and Yamaha rider James Toseland.
Toseland posted a best time of 1min 34.8secs despite suffering a fall during the morning when he low-sided off his R1, but he declared himself happy with how the day had panned out as he worked through electronic settings on his bike.
"It's nice being on a track I know so I could really concentrate on the bike, unlike Portimao in the last test where I was learning the circuit as well," the former champion said. "I think we've been really competitive today, the times I've been doing have been really comfortable, so a sign for me that the bike and team is working well.
"We've been mainly working on the electronic side of things today. It's such a new bike, there were a lot of things the team wanted to try out during the 2009 season but didn't have time to do, so the team are taking the opportunity to try some new things with a new rider to see if there's an improvement."
Jonathan Rea also suffered a fall aboard his Ten Kate Honda but still ended up fourth quickest from reigning World Supersport champion Cal Crutchlow while BSB title winner Leon Camier rounded out the top six.
Kenan Sofuoglu headed Ten Kate team-mate Michele Pirro amongst the two World Supersport runners on track despite crashing during the morning.
Jakub Smrz wasn't present - despite reports that he was going to test an Aprilia RSV4.Superbike:
1. Leon Haslam
(Suzuki) 1min 34.5sec
2. Max Biaggi
(Aprilia) 1min 34.7sec
3. James Toseland
(Yamaha) 1min 34.8sec
4. Jonathan Rea
(Honda) 1min 34.9sec
5. Cal Crutchlow
(Yamaha) 1min 35.1sec
6. Leon Camier
(Aprilia) 1min 35.8sec
7. Max Neukirchner
(Honda) 1min 35.8sec
8. Sylvain Guintoli
(Suzuki) 1min 36.1secSupersport:
1. Kenan Sofuoglu
(Honda) 1min 36.8ec
2. Michele Pirro
(Honda) 1min 37.1sec