justin_o_guy2 wrote on 09/03/22 at 13:38:15:Looks like the throttle cable is either adjusted short or the throttle just isn't closing. The plate the cable is attached to? See how far the idle adjust screw is from touching it? You are idling at almost quarter throttle.
I would pull the fuel line off the carburetor and see how fast fuel is being delivered to the carb.
Make sure the kid plugged off the vacuum line that the OEM petcock used.
If that fuel line is skinnier than what it calls for, you won't get good fuel delivery
Aaand
If the kid bought a cheap knockoff petcock instead of the Official Yamaha ,about thirty dollar petcock, it has skinny plumbing and will not deliver.
If you don't do the tests,you won't know what is going on.
Looks like you have a petcock that should be in the trash, maybe not.
You have to Prove fuel delivery to the carb.
Without that, it can be a new,perfect carb,and it's Not gonna run wurfacrap.
If he didn't plug the vacuum off,not gonna run wurfacrap.
If he didn't remove the shipping sleeves from the petcock.
Step One
Check fuel delivery to the carb.
Establish That.
If you establish that you have sufficient flow through the petcock and your fuel line to make the engine happy, connect the line to the carb and open the bowl drain and catch it in a measuring cup. Time it to a half cup.