Just days after the unexpected announcement that he will leave Yamaha at the end of this year, Ben Spies was back on track in front of his home US fans at Laguna Seca.

The Texan, who will be seeking his first US GP podium on Sunday, spent time working on used tyres during the two Friday practice sessions and was pleased with the outcome.

Spies' best lap of the day put him in fourth place, 0.620s from Repsol Honda's Dani Pedrosa, but just 0.286s from Yamaha team-mate Jorge Lorenzo.

"Today was good, we worked on a lot of laps on the soft tyre in the morning when the track wasn't so great but not too bad either," said Spies.

"We did a lot of laps on the old tyres and the bike was pretty quick so I'm happy with that.

"The bike's got a good balance, we just need to fine-tune it to get a few more tenths out of it, but I think for race pace we're looking good."

Spies is yet to announce his 2013 plans.