Hello! I bought a used FZ07 and need a bit of advise

[collinjet]

I guess what Im asking is, if the engine isnt running but the lights are left on, why would it not start once I tried to start it. Does that make sense? Like the engine tries to kick over but it then seems like the battery is dead. I would think it could have the lights on for 20+ minutes before the battery died?

[mossrider]

Just now, collinjet said:

I guess what Im asking is, if the engine isnt running but the lights are left on, why would it not start once I tried to start it. Does that make sense? Like the engine tries to kick over but it then seems like the battery is dead. I would think it could have the lights on for 20+ minutes before the battery died?

Still confused, it's late.

If it ain't running the headlight ain't on (others are inconsequential). If it ain't running because the key is turned off there should be no drain on the battery, ever. If you turn it off with the kill switch and left the key on at some point you're doomed so don't do that.  

If you have the original battery and it wont sit for a half hour and still start it's time to replace it. I bet this [and not leaving it sit under drain] ends that problem. 

[YZEtc]

I, too, think your battery has seen better days. It's not uncommon to inherit an abused battery when buying a used bike, even if the rest of the bike is perfect. Just leaving the lights on and not properly recharging the battery afterwards can do that, or parking the bike for months on end and not keeping the battery charged during that time.

I'd also buy a new OEM air filter and change that, too. That's an important thing not to neglect.

[collinjet]

I did just replace the air filter. A mouse took a bunch of seed in it sadly.