Edwards hails pneumatic valve engine

The American shrugged off a troubled time in first practice, where he and teammate James Toseland ended up at the bottom of the timesheet, to be one of the quickest men in the dry afternoon session.

And he was delighted with his experience of the power unit upgrade, which he thinks will help lift his team's performance.

"This morning was a bit of nightmare and I couldn't understand why," explained Edwards, who finished the session third after briefly topping the times. "The bike wouldn't go anywhere.

"It was spinning but we found something before this afternoon and just got going. I felt good immediately with a setting that is pretty much what I've run in Qatar and Jerez.

"But the new engine is phenomenal. It is so good and I'm so happy. With the old engine when you went from third to sixth gear it didn't really go anywhere. Whereas now, every time you shift a gear it feels like it's building more steam.

"I got behind Valentino (Rossi) and for the first time I can remember I was able to stick with him on the straight. Normally he'd just get smaller as he disappeared into the distance. We have been lacking three-tenths at a track like this with a long straight, and now we have it in hand and it feels good.

"So I'm really, really happy and thanks to Yamaha because it is a big improvement. I've done some pretty consistent runs on used tyres but I always go good at this track. I feel comfortable and the bike and engine feel fantastic."

Toseland had a less successful day, as he got to grips with learning the Estoril track for the first time. Matters were not helped by the wet weather in the morning and an early session spill in the afternoon.

However, the Briton was still fairly pleased with how his day had gone as he ended up 13th overall.

"It is quite a difficult track just on the basis that you have got such tight corners, particularly at the end of the high speed straight where you have to get the braking point for the slow first corner dead right. Then there's the tricky chicane, which you just have to ride round and round to get the hang of it.

"A cold tyre caught me out on my first lap this afternoon. I think with the rain this morning the track wasn't so clean. I went into the corner steady and at a pace where you don't even think about crashing. Next thing I was on sat on my backside and twisted my right ankle again that I hurt in testing at Jerez.

"But I'm really happy with progress. I'm not too far off already and we effectively lost a session this morning with the weather. The new engine is definitely better. It has more acceleration and the lines you take are different because the power comes in quite aggressive when you are hard on the throttle.

"But you can exit the corner better with the extra power. It is a big step forward and I'd like to thank Yamaha. They always said the latest we would get the engine was Estoril and they stuck to that promise."