Casey Stoner may have been fastest in both of Friday's free practice sessions for his home Australian Grand Prix, but he was far from fully satisfied.
The Repsol Honda rider, chasing his fifth home win in succession and a possible second world title this weekend, has won for the last four seasons at Phillip Island on a Ducati.
Stoner's RC212V debut saw him finish on top of the timesheets by 0.269sec from title rival Jorge Lorenzo, but both riders lapped slower in the second session.
"I don't feel totally comfortable with the bike today and I'm sure we can improve the bike a lot," said Stoner, who suffered a small fall in FP1. "The track is certainly a lot more bumpy than last year and I think it will be very difficult to get the bike feeling 100% as the circuit is making things worse.
"In general we've found the Honda is better in certain aspects than what we had last year but with these bumps it's difficult to compare in other areas. We need to get the bike riding the bumps in the front a lot better, and also find some more rear grip. There is still a lot of work before we find the right race set up and we know we can go a lot faster".
Team-mate Andrea Dovizioso also complained about the track surface.
"It's been a difficult first day of practice," said the Italian, who was sixth fastest. "The track has many more bumps than last year and it's difficult to see them, maybe because the surface is very dark I don't know, but I've been struggling to get a good feeling with the front.
"I decided to keep the hard tyre in front because it suits my riding style more, but with these bumps it's impossible to control the bike and when I switched to the soft front tyre I couldn't improve my time either. If the temperature drops tomorrow it will be even more complicated, but we will try our best to improve and have a good qualifying session".
Dani Pedrosa, winner last time in Japan, could only manage seventh on the combined timesheets, one second from Stoner.
"In the morning I began calm just to get the feeling with the track and we did a decent time, but in the afternoon I struggled a lot with the rear grip, the bike was spinning a lot and we couldn't fix it during the session," explained the Spaniard.
"The fact that my lap times are practically the same in the morning and in the afternoon is a sign that something is not right. It's a pity because maybe tomorrow the weather is not as nice as today, possibly colder, but I trust my team and I hope we can improve.
"The track is also very bumpy, much more than last year, which makes things even more difficult, there are many places where the wheels are off the ground. Anyway, we will try to make some changes on the bike and I will do my best to improve my riding and let's see what we can do tomorrow".