How about the end of first gear, and the end of second gear?

If the engine will rev through first and second, but not third; then more than likely the carb has more gas going out than coming in. This may not be an issue in first and second, as you are not in first and second as long as in third.

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
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