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  • Writer's picturePaul

Elite RIO Gold Fly Line with New SlickCast Coating Review

Updated: Nov 1, 2021


All fly lines are not created equal. Whether it be different cores, tapers, compounds, or other variables, lines can range from basic and affordable to advanced and ultra-high performance made for specific applications.

RIO is undoubtedly one of the leaders in the fly line game, and seemingly every year they are introducing brand-new features and line designs. However, this year things are even more interesting than usual. Would it pique your interest to hear that RIO has introduced a line technology that is said to be "probably the most significant technology introduction the fly line world has yet seen"? How does that grab your attention? Read on to find out more about the new premium-level Elite RIO Gold fly lines — one of several lines now featuring the revolutionary new SlickCast coating!

Line Specs: WF4F and WF5F

Tested Color: Moss/Gold/Gray combo

Overall Length: 90 feet

Head Length: 46 feet

30 Foot Grain Weight: (WF4F) 126 grains / (WF5F) 146 grains

Full Head Weight: (WF4F) 175 grains / (WF5F) 208 grains Core: ConnectCore Plus

Welded Loops: Yes (2)

Price: $119.99 each

The term "game changer" is thrown around a lot these days in marketing materials and advertisements, but that catchy phrase sounds like it could legitimately apply to lines featuring SlickCast. Check out these quotes from RIO that strongly back this new tech...

"...tests conclusively show that lines built with SlickCast have the slickest, most durable coating on the market — producing the least amount of friction ever measured on a fly line."

"SlickCast creates the slickest and most durable fly lines in history. Lines built with SlickCast out cast, and out last everything we have tested, and by a long way."

Fly line becoming cracked or dried-out are problems that fly anglers are constantly battling against, so these proprietary new coatings sound REALLY good to me. RIO says that lab tests show the coating to be 33% more crack resistant and over 140% more abrasion resistant than the next toughest fly line available.

The Elite-level SlickCast lines share the same basic lengths, tapers, grain weights, and some select technologies as equivalent lower-tiered lines, but also offer some worthy upgrades. Notable features include ConnectCore Plus cores for up to 30% less stretch than standard cores, MaxFloat high-floating tips, the SureFire tri-color marking system to help differentiate line sections, DualTone which marks each line's "sweet spot" for rod loading, and EasyID which puts the line designation right on the line itself. Of course, there are also welded loops on each end.

No surprise here, but my test lines had no flaws in craftsmanship — smooth, clean, and the loops were perfect.


Right out of the box my test lines were VERY slick. I definitely felt casting was made easier as the friction was noticeably low. This is all great, but what about in the long term? At the time of this writing, the WF4F line (the one I've used the most) has been used on about four total trips and remains super slick, but that's not saying much.

The real test will come after several months, and I'll provide an update at the bottom of this review later this year after the line(s) have accumulated far more hours of use.

About the first 20 feet of fly line is moss-colored which transitions to gold...

SlickCast is said to constantly release slickening agents which migrate to the surface of the line. This should maintain a certain level of lubrication to prevent drying/cracking and also maintain a high level of castability. But, does this mean that these lines NEVER have to be dressed ever again? I sent that question to RIO and was told that it depends on things like environmental factors or abrasion which can remove some of the slickness additives. While it was said that the lines "will continue to perform well for a long time without dressing," a dressing can be applied if there is a noticeable drop in performance.

RIO Gold fly lines have 30-foot head weights not as heavy as the fast-action-rod-friendly Grand series. My WF4F and WF5F samples were built just 6-grains heavier than the "ideal" 30-foot head weight per AFFTA standards which makes them versatile for all types of rods, but even more optimal for slightly softer rods like medium or medium fast action.

...and the gold transitions to a gray running line.

I'm no stranger to Gold lines and really like the smooth, easy-casting nature of them. I actually have been using this line on a fast action 4-weight and have had no complaints as far as performance goes. Here in Florida, I do find that I can fish non-tropical lines like these generally with little to no problems if there's some cloud cover or the sun is at an angle, but during the middle of a sunny summer day a tropical line is often necessary as a "normal" line will get gummy and cause MASSIVE casting frustration! I think the added slickness has also helped these lines perform a little better in our hot, sticky weather.

The different colored line markers these are designed with look cool and likely will be a benefit to some, yet I honestly pay no attention to them at all. The low-stretch ConnectCore Plus is a solid addition that everyone should find useful, as it makes hook-setting a little more efficient. This new core seems like it has a tad more stretch than the original ConnectCore that I tested right here, but the handling has also improved.


I'm looking forward to seeing if the long-term tests live up to the hype, because as I'm sure most will agree, I hate having to dress and clean lines. Hopefully SlickCast alleviates the frequency or need to do so altogether. SlickCast coatings are now available on both Elite Tier and Premier Tier Gold, Grand, Perception, and Technical Trout fly lines. Expect more in the future. Lines in the Premier Tier are priced at $89.99 while Elite lines run $119.99 each.

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