Nicky Hayden posted his best lap of the three-day Qatar MotoGP test on the final day at the Losail circuit on Sunday, but continues to struggle for outright power on the RCV1000R.

The Drive M7 Aspar rider set a time of 1m 56.273s, an improvement of sixth tenths over his fastest lap from Saturday as he finished ninth and leading Open class Honda rider.

His time was 1.399s down on Forward Yamaha's Aleix Espargaro and Hayden has outlined the need for a significant boost in top end power as he continues to lose out by up to half a second on the straights.

"It's not right that we should be losing half a second on the straights. We know what HRC is capable of so I am confident that we will soon have some more improvements," he said.

"As far as we're concerned we will continue working to get all of the potential out of this motorcycle.

"In the end I set my fastest time of the test, which is positive even though the gap to the top is still very big, especially when you consider that the top riders are not here," he added.

"We have worked hard and found some good things but we still need to take a big step forward in terms of the power."

Hayden's team-mate, Hiroshi Aoyama, was one place behind in tenth with a lap in 1m 57.006s.

"Little by little we have improved during this period and I have also tried to adapt to the team and to my new bike," said Aoyama, who also clocked his best lap late in the evening on the final day.

"This weekend's test has been very important because in two weeks we have the first race of the season here. Tonight [Sunday] we have tried to improve the setting for the race and we have also been able to improve the feeling in corner exit, which has been a problem here for the last couple of days.

"In general am happy with the way we are moving, we just need to get the bike turning a little bit better so that I feel more confidence in the corners."