Personally I think its worth checking how the rectifier is mounted up, if the back surface isnt securely mounted againt the subframe then it can lead to overheating of the rectifier, which then leads to blown bulbs and knackered battery. Its probably worth making a metal plate to mount it onto to, the small amount of effort it much better than the cost of a new battery and rectifier. I think the rectifier uses the frame as a heat sink.

I bet 85% of rectifier failures on NSRs are down to the tyga tail being fitted, I had this, I think Maxim had this, anyone else?