Lorenzo 'very quick' until final hour, '17-'18 mix difficult

Jorge Lorenzo helped draw a line under a lowly 22nd on the final day in Buriram by leading substantial parts of the opening day of MotoGP testing Qatar.

Unfortunately for the Ducati rider, when temperatures began to drop during the final hour so did his performance and he ended up fifth fastest, although just 0.370s from Yamaha's Maverick Vinales.

"Mainly the track changed [compared to Thailand] and together with the track I improve the results," Lorenzo said of the difference in his performance.

"I could be very quick from the beginning with good pace until the last hour when the temperature of the track went low and humidity increased. Then I didn't have the same feeling. So we need to understand why.

"Also we changed the tyres and all the feeling changed. But until the last hour I was very competitive and led the classification for a few hours.

"I feel much better now [than Thailand]. But I repeat we have to understand what happened when the temperature went down, because we struggled more than the rest. And I would like to improve a little bit the feeling on the front, in general."

Lorenzo had called-up a 2017 Ducati to try alongside the GP18 to help understand the root of his issues in Thailand and later said he needed a 'mix' between the two.

For Qatar, the triple MotoGP champion had some chassis parts aimed at mimicking the feeling of the GP17, with the new GP18 engine.

But it wasn't a success and Lorenzo stuck with the standard GP18 on day one.

"Here I don't have completely the 2017 bike, I have a chassis that wants to simulate the performance of the 2017, but today it didn't work like that.

"So it's going to be complicated to make a mix between the engine and the chassis.

"So for the moment we are concentrating and focussed on the new bike and I think we have some margin to improve.

"The new bike I think has potential, we need to understand the way, to get this perfect potential. Still be don’t find it."

Team-mate Andrea Dovizioso was second fastest.

Two more days of testing remain until the start of the new MotoGP season.