01 Mille electrics dead, bike won't start. Solenoid?

Evening folks, long time lurker here with a bit of a problem.

Took the bike out today for a 10mile run to work with no issues. Left work and travelled a couple of miles to my parents house again with no issues. When I came to leave, thumbed the start button and the bike died, no starter, no dash display apart from the rev counter needle "ticking" slightly.

The battery was fully charged and lives on an optimate, the battery is less then 10 months old and is the larger, higher powered battery - as recommended on this forum.

I checked all the connections and fuses, everything in good order including the brown connector along side the seat. Checked the battery voltage and it's showing 12.9 on the multimeter.

I left the bike to research the problem and returned a few hours later, reconnected the battery and turned the key. The dash lit up but had been reset (reset clocks etc) I pressed the starter to see if it would fire up and it killed everything again with just the rev counter needle ticking. It's now sitting in my dads garage in bits.

What do you think might be the problem? Could a failed starter solenoid cause this or something more sinister?

Cheers
Dave

Thanks for the reply. Done some investigation today. Checked and cleaned the earths, battery connections and other connectors and charged the battery. The bike now clicks into life when the key is turned and the dash lights up. Even better - the things now fires up so I guess the battery was too low.

I checked the voltages:
Battery with ignition on but engine off: 12.8v
Battery with engine running: 14.2v and maintains that voltage with lights on, fan on and when revs increased.

I also checked the cables going into the brown plug with the engine running and wires disconnected the meter showed 22 vac and with engine off 0.1 ohms on any three wires.

So, the earths are good, the solenoid is good and I seem to be getting some charge to the battery but the 22vac on the yellow wires means something isn't quite right?

What should I do next?

Cheers
Dave