I had the same issues with mine and i went to the dealer and told them there was a problem with the loom and regulator and rectifier, they said they had never heard of it, i went armed with a few pages from this forum, the next day the dealer rang me and said yamaha have agreed to change the loom and regulator rectifier, i asked is there any chance they could cut the loom under the tank solder the wires and shrink wrap the cable as i didnt want a new loom as it was a pain in the arse, the dealer refused and said they loom needed changing, after two weeks i had a new loom reg/rec changed and the bike is now running great, if you want any help from me, you can give yamaha uk my number and i will explain that there is a issue.