rocket III classic won't start

Are you saying it spins and spins but literally has no spark??
If it spins but has no spark, I don't see how it could be the battery.
Kill switch?
When mine would start and run fine one time, then be harder to start and run like crap the next it turned out to be a loose 30amp fuse holder. 4 bucks at NAPA fixed it. Chased that for a looooong time.
At 33K miles, have you checked valve clearance? Too tight of valve clearance can affect cold starting.