I would suggest building whatever carbs you decide on perfectly stock. This way you have a repeatable baseline.

As for cutting coils on springs, I don't. Of course we have lots of different springs to choose from, so not really a problem.

However, if you use the Carter YF's that you suggest you have; AFB spring kits (readily available) may be used in the the YF.

Jon.

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