Cutting Out When Warm

[nkaminar]

If you still have the screen in the carburetor, that could be clogged too. To test the whole fuel supply system, remove the drain plug on the bottom of the carburetor and turn on the fuel to see if you get a good steady flow out the bottom of the carburetor. Again, do this outside and with a fire extinguisher handy.

Because you got the same performance with two different carburetors, the problem is probably not in the carburetor, but upstream.