To cast bass flies, use a line one or two weights over the rod’s “official” rating.
Most rods will cast a bass fly much better with a line one or two weights over the rod’s “official” rating. Bass casting is some of the most challenging fly casting there is. We throw heavy flies 45 to 60 feet (often into wind) and do that hundreds of times a day. That requires plenty of line weight up front to properly load a fast- or medium-fast-action rod. For bass fishing, if you only use the the line weight marked on the rod, you are needlessly handicapping yourself by trying to cast with an underloaded rod. Properly loading the rod with more line weight allows modern graphite rods to properly flex and propel a heavy fly with the least amount of effort. It has nothing to do with your personal casting style or what a shop clerk says, it’s basic physics– everyone will cast easier with more line weight.
If you’re an average or intermediate caster, use a line two weights over the rod rating. Only go down to a line one weight over the rod rating if you’re a bona fide expert caster and can double haul. By the way, I can double haul pretty well and I still use lines 2 weights over on most of my rods, especially when I’m fishing tighter places where most of my casts will be 45 feet or less.
Just remember, this heavier line rule only applies to floating lines. Sinking lines, with their weighted cores, are generally heavy enough, so use sinking lines rated the same as the rod’s weight. And if you don’t believe me about the two weights over concept, borrow a heavier line and try it on your rod. I think you’ll almost certainly find it casts easier.
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