Perception: RIO Solves the Low-Stretch Riddle

RIO's new flagship trout line has made a core change, both figuratively and literally. The Perception trout line ($89, rioproducts.com) has a new low-stretch core—the first of its kind for polyvinyl chloride (PVC)-based fly lines. RIO won't say what its proprietary new core is made of, but it's NOT nylon monofilament or nylon multifilament, which are the traditional elastic materials for PVC fly line cores. And it's not kevlar, a failed zero-stretch product from more than a decade ago that had memory problems and incessant coiling. No, this is something completely new, and it's also something you'll notice right away when you cast and fish the line.

If you've fished RIO's InTouch Deep lines, you've already felt the difference a low-stretch fly line can make to your contact with the fly, your sensitivity in detecting strikes, and your ability to set the hook when your feel the fish. Everything is more instant and efficient. But does it make a difference in your casting as well?

"Absolutely," said Simon Gawesworth, RIO marketing manager and a big part of the Perception design team. "We did many double-blind casting tests, and experts casters like Jerry Siem and others could pick out the low-stretch core every time. And they prefer it."

According to Gawesworth, a good caster can significantly stretch a standard fly line in the air by merely hauling the line, and this stretch is like a giant power drain when you're trying to move the fly efficiently. The Perception's low stretch—about 6% compared to about 30% in a standard fly line—lets you move the fly immediately instead of first stretching the line before you can move the fly.

We've tested the line extensively in the months preceding the official announcement of the new product, and found that it not only casts better in the air, it mends more efficiently, picks up quickly and quietly, and gives you better control and more sensitivity for "blind" fishing subsurface with nymphs and streamers, where instant contact with the fish is the difference between hooking up, and missing a strike. What's more, RIO has carefully avoided the shortcomings of previous PVC no-stretch lines to come up with a line that has little or no memory, and so far, excellent durability.

The line has the same slick, high-floating coating as RIO's other premium lines and has welded loops at both ends. The major cosmetic difference is the tri-color coating—RIO has offered bi-color lines before but this is the first one with three visual markers. The first 20 feet of color helps you track the fly and measure distances when you are fishing close, the middle 16 feet shows you the best loading point for efficient longer casting. Perception lines are available in WF3 through WF8-weight lines in both light green/camo/tan and camo/tan/gray color options.