MOTEGI, JAPAN, OCT 1 - The success Nicky Hayden had in finishing third in Aragon, Spain two weeks ago didn't follow him to Japan.Instead, Hayden struggled in Friday morning practice at the Twin Ring Motegi circuit, suffering a minor get-off on his way to finishing the day 13th out of 16.Hayden didn't complete one lap before he had to return to the pits with brake problems on his Desmosedici GP10 to switch to his second bike.Late in the session the team made some changes and "immediately the bike felt better. I did my best lap my first flying lap and then second lap up in the hairpin, over the bumps, I just kind of hit the bump and had saved it and then I just had so much lean angle I basically just fell off the inside of the bike," he said of the crash in the Turn 10 Hairpin, a 35 mph right that leads onto the back straight. "I mean, the slowest corner on the track. It was a real easy crash and nothing to really say. I mean, I don't think it hurt the bike too much. But it did take in quite a lot of gravel, so I didn't want to ride it back. And the handlebar was broke too. And that was it."Bit of a bummer, because I'd just got it going and lost quite a bit of time, actually, because it happened at the end of the session, but there was still...only did 18 laps, which wasn't a lot. Would've been nice to learn a bit more."So we started off in a bit of a hole. But I'm 13th or something, but my ideal time was seventh. And they could see on the data already in the three or four corners in that split before I crashed, I'd also took off another couple tenths. So that if you're looking for something positive, that's pretty positive. Actually, the bike didn't feel so bad and definitely started in a bit of a hole, but overall, not a disaster.The Ducati was hardly changed since the Aragon race, except for stiffer front fork spring to help with the man hard braking, downhill corners.Part of his success in Aragon was down to the track surface being smooth. The Ducati has had a hard time soaking up bumps all year, and the brand new Aragon tarmac was pool table smooth, Hayden said. The Motegi surface seemed slippery to Hayden, but consistent, except for a few spots that were wet. "There was one place, Turn 7, you were quite leaned over on the brakes. I was picking it up across it and it was a little bit sketchy."Repsol Honda's Dani Pedrosa crashed in the corner before the hairpin, breaking his left collarbone into three pieces and essentially ending his title hopes. Puig's manager Alberto Puig said the fly-by-wire throttle had failed and the throttle had stuck open, something Hayden experienced in the very first session of his very first grand prix at the Suzuka Circuit. There was also water in the corner where Pedrosa crashed, Hayden said, but "on the inside. I was going around it, but I don't know, maybe in the second lap was quite low or maybe he didn't see it. In the day time with the dark shield on, it took a little bit to see it. But that one you could miss. On the entry to Turn 7 you almost have to go through it. There was not a way round it."