Georgeb, my bike is now in it's fifth week in my local dealer to have the reg/rectifier issue sorted. In my case the terminals have not made a good conact and have burnt. You need to raise this issue with Yamaha UK and insist on a proper solution, 'cos the next time you might not have enough ooooomph in the battery to get going again even if you do know what the problem is.
Everyone who has had this problem need to register this with Yam UK on 01932 358042 and ask for Don or Moira.

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