The most important factor, IMHO, is to tell the frame builder what you want to us the bike for and for what sort of riding. Unless you really know what you want in a frame, I would leave it up to the builder.
@yoav started
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The most important factor, IMHO, is to tell the frame builder what you want to us the bike for and for what sort of riding. Unless you really know what you want in a frame, I would leave it up to the builder.