This week’s Throw Back Thursday fly is the RS2, developed by Rim Chung.

RS2 - Original |

This is a recent tie, following the original pattern sheet. I’ve used natural beaver dubbing and webbing from a dun colored hackle for the wing. The first time I tied this fly was in the 1990’s and for some reason thought it was a lake fly. Wrong! It’s an imitation of a mayfly emerger. Like any great pattern, just change the size and color to imitate the real bug.

As I was developing my Crooked River Flies page, I was reintroduced to the RS2 and I thought it was a candidate for a Throw Back Thursday Flies post. So here it is!

I like to develop a little historical piece to accompany the post when I can. But Bill Seitz, our resident expert on the Crooked River here in Central Oregon, did it for me:

“The RS-2 is a mayfly emerger that was developed in the 1970s by Rim Chung (the RS-2 comes from Rim’s Sembalance, second version). It is a “go-to” fly for many anglers that fish on the heavily-fished tailwaters of the Front Range of Colorado. It is a versatile mayfly emerger pattern with application on all Central Oregon streams. Dave Hughes, in his book Nymphs for Streams and Stillwaters, recommends fishing this fly in the upper water column (12 inches to 2 feet) in combination with a slightly larger fly about 12 inches from the RS-2 using an indicator or a dropper.” 

Here is one of Bill’s variants to the RS2 to allow more fish caught per fly…black UV Ice Dub and Zelon.

RS2 - Black Ice Dub |

Have you ever fished this fly? 

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  1. RS2 in 18 is long standing go to fly for the San Juan River in New Mexico.
    Fished there in choc brown and gray. Tied with thread body and white foam instead of Bill’s Zelon. No tail.
    Thanks John

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