Why don't you try to get a contact in Japan directly? I think that most of the dealers must speak English. I have a friend that had some problems with a new Yamaha (produced a lot of smoke at the start), and spent some months here in Spain going to official workshops without getting the problem fixed. So he wrote a letter of complaint and sent it directly to Yamaha Japan. In a month or so he received a call and was asked to take the bike to a nearby Yamaha dealer, where the factory had sent a japanese technician, who spent all day working on his bike and fixed it without additional cost. This happened 20 years ago, why should't be possible today?
If you get a local dealer which can bring the parts from Japan you will avoid the paperwork, and possibly that local dealer could get better shipping prices, but then you would have to pay for his services, so trying to get the part directly from Japan, nowdays with these new technologies, may give results, don't you think?
Now Kawa KLE500 dirty-knobby tires, noisy Thunder exhaust.
Waiting for the new 2008 Yamaha XTZ660 Ténéré