Hello all. I have an issue with my charging system. I was riding today when I noticed that my speedo needle went back to zero, and came back on after a few minutes. The engine fault light came on and disappeared, and my voltmeter tells me that it's pulling over 16 volts, the needle is at the upper-end of the gauge. The bike will not idle now. It konks out immediately when I let go of the throttle. Something that it's never done. Any suggestions appreciated folks.

There are a few tests you could do to test the system ,, but this straight away points to a bad regulator ... High voltage , (as you seem to have), can play havoc with all sorts of electronics , (as you also seem to have)... First off,, check cables and connections to regulator ,(your reg is earthed to the frame , check that connection also),,,,

Get a digital Voltmeter ,,, Place Voltmeter across battery terminals and leave it there for this test ...... (what is the voltage ? ),,,,,, Start bike, (what is the lowest voltage at start up ? ),,,,,, At idle , (what is the voltage? ) ,,,,, At 2000 rpm,(what is the voltage ?) ,,,,,,,, Now the big test ,,,, what is the voltage at 3000 rpm ? ,,,,,, If voltage is above 15 volts at 3000 rpm , (or any time),, your regulator is bad ......
As you fairing voltmeter, (which is a reasonable indicator),, is showing 16 + volts ,, the digital voltmeter will tell the real story .......

Thank you sir. Appreciated.

Another consideration is a faulty speed sensor which can make your speedo go back to zero, cause idle/stall issues and throw a fault code. Need to check what fault code you got. Not to say that mark isn't right either

Thanks fatbat.

Neale ,,,, Seems like you may have had success with your fault finding efforts ,,,, After your fault finding ,, what was the problem ???

HH at Blacktown rang to say my new voltage regulator has arrived, I will pick it up Saturday. I will let you know.

Problem solved. $335 later. Thanks for the helpful advice, appreciated.

Nicely diagnosed MW.