It is (or was) a fairly typical defect, mostly (but not exclusively) on earlier Italian built 08/09 bikes and perhaps a few 2009 models registered in 2010. It was usually the earth pin that melted in most cases due to a poorly fitted connector. By no means were all bikes from that era were affected (mine's an 08, which I've had from new, and its still absolutely fine.)

Yours is slightly unusual in that's it's a 2013 bike. I think everyone was under the impression that situation had improved since Yamaha became more aware of the problem and they had got better at fitting the connector, and that dealers had become more vigilant during their PDIs. Obviously not all production line workers and dealers are being watchful of this? Or maybe your bike's an earlier one but registered in 2013?

Just out of interest, what's the country of manufacture on your VIN plate under the seat?

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