New Factory Yamaha rider Ben Spies was the only non-Honda rider in the top six, during day two of the Sepang MotoGP test.
Spies, whose opening day workload had been interrupted by an early fall, more than doubled his track time on Wednesday with 60 laps.
The best of those came in the cooler morning conditions and was good enough for third, behind the Repsol Hondas of Dani Pedrosa and Casey Stoner, on the final timesheets.
"Today went really well,” said Spies. “We started out and got right up to speed. We worked pretty much just on electronics and also evaluated a couple of different engine configurations, both of which worked really well.
“The lap times were pretty similar so we need to work out which direction we want to go. We got a lot accomplished today, tomorrow we've got a couple more things on the engine to look at and we're going to try some tyres for Bridgestone."
On the other side of the garage, world champion Jorge Lorenzo tried his second new chassis in as many days, but felt the first one was better.
Lorenzo, who rode for 35 laps, was seventh fastest.
“We tested another new chassis, which had some positive and negative things compared with the chassis we tried yesterday,” said the Spaniard.
“The positive is that we have more traction, but we had some little vibration in the braking.
“In terms of the engine we tried some electronics, but still without [a complete] solution.
“I'm only worried about my riding and giving the best explanations I can to Yamaha, to help them move forward,” he added.
“It's normal in development to find some things that don't necessarily work so well and today we found one,” admitted team manager Wilco Zeelenberg. “At the end of the day it has been positive and we have more valuable information for tomorrow."