Greg recommends 14 gauge straight gauge spokes.
I respectfully disagree. Butted spokes, with their thinner section on the straight portion where there is only tension, not shear, force, go a very long way in preventing damage at the elbow of the spoke, the flange of the hub or the spoke hole in the rim. This is especially important when using a hardened rim like the GP-4. A stronger spoke does not necessarily make for a more durable wheel, at least in my 30 years of wheelbuilding experience.
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