Starter Clutch chain came off

Bit of a weird issue here and I'm not exactly sure how it happened. I came out to replace my left side cover gasket. When I took the cover off I realized the chain was off. I've attached a video below:

VIDEO


I suspect my dumbass brother was out here messing with it, but getting him to fess up is another issue..

Is there a way to get the chain back on without pulling the flywheel etc? I tried cranking it with a socket on the flywheel bolt and it fed the chain back around most of the way, but not completely. It's now pretty stuck in that position, wondering if it just needs to be disassembled at this point.

Seems like to me that you should be able to remove the starter sprocket, reinstall the chain and put the sprocket back on. If ere is not enough chain slack for that, you should be able to loosen the starter motor and tilt it a bit to get the sprocket back on.

KZ400?

If so, then you may have to unbolt the starter motor and slide it towards the clutch-side of the engine. Also slide the sprocket off of the starter motor shaft. Run the chain around the starter clutch sprocket and thread the starter motor sprocket onto it as well, then you should be able to reinstall the sprocket on the starter as you slide the starter back into place. It is not necessary to completely remove the starter.