Valentino Rossi believes the first day of Sepang testing was largely a waste for him due to the track and weather conditions, and a tactical error.
The former champion was only eighth quickest on his Ducati, as the field managed limited dry running before rain hit the Malaysian venue.
"It's a bad day because we didn't have enough time for our work," Rossi told the official MotoGP website.
"We were also a little bit unlucky because this morning I went out very, very early but the condition of the track was bad - dirty and slippery from the cars of last week. When the conditions became better, we already had more than 20 laps on the tyre. We decided to wait for the afternoon to use the other good tyre but unfortunately the afternoon had rain.
"So it's not a very important day, except the work in the wet, because it's the first time that we've tried the new bike in wet conditions, and the feeling is not so bad, like last year with the old bike. From this point of view, in the wet it was good, but in the dry we didn't understand anything."
Rossi added that Ducati had a large jobs list for this test even though it had not brought many new parts.
"We don't have a lot of new stuff, but especially we're trying to work on acceleration, where we lose quite a lot, with some new systems and traction control, and we have to work on the forks and the rear shock with some new things," he said.
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