Weird starting problem

[megamile]

2011 Hannigan Venture, ridden every day since purchase 9/2024. On vacation for 3 weeks; trike was parked and covered. On return, trickle charged battery to 12.5 volts, turned key; everything looked normal. Neutral light, clicking fuel pump, dash lights, 12.3 volts on voltmeter. Touched started switch; all power died. Thought I popped main fuse. Nope. All fuses checked good. Key goes to off; turns to start, power returns and 12.3v. Touch start button, power dies. Key to off, then on; power returns. Pulled and checked battery and cleaned terminals and connectors; all seems good. Trike started and ran well daily until I parked it; maybe it's mad at me for going on vacation without it? Wondering where to look first. Switch? Starter solenoid? Wires to starter? Starter short? Clymer is no real help at this point... Mostly it assumes that bike turns over. No clicking or anything; just completely loses all electrical until I recycle key. Weird.

(Also posted in Delphi Yamaha forum.)

Anyone have ideas?

[vzuden]

Check the starter solenoid and main ground for clean and solid connection.   If they are good, pull battery and take to auto parts store for load test.  Beyond that, possibly a bad connection in key switch or starter button 

[Marcarl]

Sounds like a poor connection.  Check battery with volt meter, 12.3 is not a good full battery but should start it at least. Try to start it and if everything dies then don't touch anything but check the voltage at the battery, first the posts then the connectors and then the solenoid. Seeing as everything dies I would strongly suspect a poor connection in that area. Note: Do not turn anything off when it all dies, check things when 'under load'.