150cc gy6 troubleshooting

[geokjones]

Hello everyone, newly registered here, thought I'd start off with a problem I'm having.

I had a nice Genuine Buddy 125 as a daily driver that was unfortunately stolen. Not much progress in recovering it, so i scrounge up a few bucks and bought a chinese 150cc with a gy6 off of facebook (hindsight is 20/20) and after about 40 miles the thing crapped out on me. Motor locked up, wouldn't spin at all.

I work for a towing company so I was able to flatbed it back home.

After the flatbed ride, I can get the thing to turn over and run but it makes a horrible noise that I cannot identify, and I was hoping I could get some insight on what's going on with it. I'm mechanically inclined enough to replace whatever needs to be replaced but I'm not experienced enough with them to diagnose it. Money is tight, which is why i bought this thing in the first place, so I'd like to replace a part or two rather than the whole motor. What do you guys think? I'm leaning towards crankshaft bearing but I have bad ears (partially deaf).

Here's a video of it starting up and running for a bit:

I appreciate any and all insights. Thanks!