Hamilton’s best time of 1m 33.278s was just two-hundredths down on the winter benchmark at Sakhir, set by Williams’ Felipe Massa on Saturday. The teams’ next track outing will be opening practice in Australia in less than two weeks’ time.
“It was a tough start to the day,” said Hamilton after an early gearbox problem, “but they managed to get the car turned around for me to complete some good laps in the afternoon, which was a fantastic effort. There's so much to learn with these new cars; it's just mind-blowing and I don't think anybody can be fully ready for the challenge of this season. But I feel as ready as I can be and I'm looking forward to seeing where we are in Melbourne.”
As Hamilton led the way, it was another highly productive day for Williams. Bottas racked up 108 laps, despite an engine failure - remarkably the team’s first and only on-track stoppage of pre-season testing.
“We ran a similar programme with Valtteri as we did with Felipe yesterday, starting off with some chassis and aero tests this morning,” explained Rod Nelson, Williams’ chief test and support engineer. “We did some long runs after the lunch break to look at tyre degradation before moving on to a qualifying simulation. Towards the end of simulation, and before we were able to fit the supersoft tyres, we had a high mileage failure in the Internal Combustion Engine.
“With the number of laps we have put on it, it wasn't a big surprise but it was still a shame that Valtteri couldn't get that final chance to push. However, with an overall team total of 936 laps under our belt, we are still pleased that that is the only time the FW36 has stopped on track throughout testing. We end the pre-season running feeling very happy with the car, power unit, drivers and team. Everything is working together as it should and we are pleased with the direction that the team is going in.”
At Ferrari, Fernando Alonso’s progress with the F14 T was hampered somewhat by the need for a gearbox change, but the Spaniard finished the day third nonetheless.
“The team did its utmost to carry out changes on the car as quickly as possible, but again today, we had planned to do more laps than we managed,” Alonso told Ferrari’s website. “There are a lot of things to learn with the use of the power unit to improve the performance of the car and we are not yet where we want to be. Everyone in the team is very competitive and we are working day and night in order to get all the potential out of the F14 T as soon as possible.”
Force India’s programme ended slightly early due to a suspected component failure, which meant Nico Hulkenberg, fourth fastest, wasn’t able to complete his planned race simulation. Hulkenberg was followed in the times by Toro Rosso’s Jean-Eric Vergne, who like the German (and Alonso) completed 74 laps.
Sauber had both their race drivers in action, with Adrian Sutil sixth fastest and Esteban Gutierrez eighth, as the Swiss team wrapped up their winter test programme.
“It was good for them to have this valuable time in the car,” said Giampaolo Dall’Ara, head of track engineering. “Looking back at the first test in Jerez, we had a tough programme to get through and faced several unexpected problems, which meant we lost running time. The learning curve was very steep at the first test. Now it’s a bit flatter, but there is still enough to do.”
Max Chilton was an encouraging seventh for Marussia, despite losing substantial track time to an electrical problem on the MR03, while world champion Sebastian Vettel managed a vast improvement on his zero lap count of Saturday, as he finished ninth after 77 tours of Sakhir.
"Our final day here was a mix of good and bad,” commented Red Bull’s race engineering co-ordinator, Andy Damerum. “It's positive that we managed to get in as many laps as we did, however, we did have a few problems. On top of that the amount of red flags didn't help, even with the extension to running in the evening.
“We were in good shape first thing this morning and got in 44 laps. Then we had a front-end mechanical problem, so we had to fix that. In the afternoon we were focusing on doing longer runs - race preparation - and that initially went well. We did a 17-lap stint and came in to change tyres, but a red flag on track halted our progress. And that was the shape of the afternoon really, with a lot of disruptions.
“Obviously we have had a lot of problems during testing, but we understand the problems and hope to have fixes in place for Australia. We know the pace is in the car, as we saw from Daniel's (Ricciardo) performance here; what we have to do now is put all the pieces together and establish reliability for the race in Melbourne. There is plenty of motivation in the team and we'll keep working hard over the next two weeks."
Jenson Button ended tenth after a difficult final day for McLaren. A high-mileage engine failure and some as-yet undiagnosed control electronics problem meant Button was unable to evaluate the team’s new Melbourne-spec front wing that had arrived in the morning.
Eleventh in the times was Caterham’s Kamui Kobayashi, who completed an impressive 106 laps in the CT05, while the final spot was filled by another Renault-powered runner, Romain Grosjean in the Lotus.
“We’re not in an ideal situation,” admitted Grosjean, after further power unit problems for the team. “There is a lot of new technology for everyone to understand, but even though we have stopped many times and spent a lot of time in the garage, each time we run the car we are learning something new.
"We’re all working as hard as we can in Enstone and I’m sure that Renault Sport F1 is doing the same. We now have two weeks to find a lot more performance and reliability.”
Opening practice for the 2014 Formula 1 Rolex Australian Grand Prix begins at 12.30 local time on Friday, March 14.
Unofficial Sunday test times from Bahrain
1. Lewis Hamilton, Mercedes, 1m 33.278s, 70 laps
2. Valtteri Bottas, Williams, 1m 33.987s, 108 laps
3. Fernando Alonso, Ferrari, 1m 34.280s, 74 laps
4. Nico Hulkenberg, Force India, 1m 35.577s, 74 laps
5. Jean-Eric Vergne, Toro Rosso, 1m 35.701s, 74 laps
6. Adrian Sutil, Sauber, 1m 36.467s, 91 laps
7. Max Chilton, Marussia, 1m 36.835s, 61 laps
8. Esteban Gutierrez, Sauber, 1m 37.303s, 86 laps
9. Sebastian Vettel, Red Bull, 1m 37.468s, 77 laps
10. Jenson Button, McLaren, 1m 38.111s, 22 laps
11. Kamui Kobayashi, Caterham, 1m 38.391s, 106 laps
12. Romain Grosjean, Lotus, 1m 39.302s, 32 laps