MotoGP world champion Casey Stoner has admitted he was disappointed with the results of the upgrades Honda brought to the post-race test at Mugello.
Stoner will only use his team's new engine at Laguna Seca this weekend, whereas team-mate Dani Pedrosa will ride Honda's revised chassis as well.
But Stoner said he was not convinced by the updates and had hoped for more - while acknowledging that the new engine was a step forward.
"We tested a new engine, which was very positive. It gave us a lot more smooth power and some small advantages in some areas. So we're quite happy with that," he said.
"Chassis-wise, I didn't feel anything better than what we've got now, so we're not going to be using that here.
"We tried a lot of things, to be honest, in that test, and we only found a few smaller things that gave us a little bit of a better feeling and something positive to think about.
"To be honest, we were hoping for a little bit more. But we'll see what we can do with the bike this weekend."
Stoner now trails championship leader Jorge Lorenzo by 37 points after crashing out of the German Grand Prix at the final corner and only finishing eighth in Italy following a mid-race mistake.
"It's opened up more than a little bit, and it should've been a lot smaller," he said of the points situation.
"The last two races haven't been good for us. A couple of big mistakes from me and things haven't gone so well.
"We had the pace at the Sachsenring and then at Mugello we had the pace for a podium but that was about it, and just a small mistake going into Correntaio and that was it, it was race over. We pretty much tried to salvage as many points as we could from that race and limit the damage, but it was already done."
- Casey Stoner
- Dani Pedrosa