Bike won't start - battery charging system??

[dacwr12]

I have 02’ YZFR6 w/ carburetor. My bike will not start. A week ago, I went for a ride got off then tried to ride again, but it wouldn’t start. I initially though it was the battery. I charged the battery, and then put it back on the bike. The bike started right up, I went for a ride got off and tired to start it up again. It wouldn’t start. I went to get a brand new battery, I put it in and it started up I was riding and all of a sudden my speedometer and lights just died. I kept riding then my bike backfired and cut out. I jumped my bike in an attempt to get it home. After a few block it did the same thing. I finally got it home and now it won’t start. What could be wrong? Is it the battery charging system? If so, is that expensive to replace? Or can an amateur replace the part? Any suggestion would help?

[Uesque]

Put a meter on the battery with the bike running, and once you get off idle, it should be charging at around 14 volts. If it's showing 12 or so, you're not charging and need to have someone take a look at it.