Hoping someone more mechanically inclined than I am could offer some expertise...

I have a 2006 Kawasaki STX 1200 with about 120 hours on it, just recently it has been having depowering issues (while running, the engine started choking out and losing power, almost to none, then would kick back in to full power). Now when I charge the battery the charger doesn't show its charging, and it doesn't hold a charge (the charger worked on another battery). The battery is only a few months old and has just a few hours on it, but the Jetski dies when I disconnect the jumppack...

I replaced spark plugs and fuel filters but it hasn't made any difference. Someone advised me to replace the battery again and that it could potentially be the alternator/stator, but it would be nice to have a few more opinions before throwing more money at it.

Please let me know if you have any questions, thanks in advance for your response...Kawasaki Karma!