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  • Writer's picturePaul

A Quick Test of RIO's ConnectCore Technology

Updated: Oct 28, 2021

It's seriously amazing the amount of fly lines available to us today. No matter the targeted species or your specific needs, there's a fly line that fits the bill. While premium fly lines certainly command a premium price these days, there's been some serious advances in their physical and material designs. With all of the line technology that's out there, one in particular stands out to me as being one of the most important: RIO's ConnectCore. What is it?

ConnectCore is marketed as an ultra-low-stretch core that's used inside RIO's InTouch series of lines.

Comprised of braided, proprietary material (RIO wouldn't divulge their secret sauce), this special core is said to provide better timing, hook-sets, and sensitivity thanks to an approximate 6% stretch rating vs. approximately 30% for a more "standard" core. As a big fan of using braided line on my spinning and baitcasting reels, I am very familiar with the advantages a low-stretch line can offer.

Not only can I vouch that hook-setting and sensitivity is amplified with an InTouch line, but casting benefits, too. I'm not going to overdo it here and call it a game-changer when it comes to casting, but when compared to a line without ConnectCore thrown on the same fast-action rod, I felt like the casts were just a little more crispy.

My biggest interest here was in testing the amount of actual stretch using a simple pull test. While I have several InTouch lines in my arsenal, I picked my two current 5-weight lines for some "unscientific" comparison testing: a WF5F RIO InTouch Gold and a WF5F RIO Bonefish (now discontinued).

To test these lines, I set a few standards. First, the end of each line was separately wrapped around the same sturdy base five times as an anchor point. Next, I pulled off approximately 22-feet of loose line and set a tape measure on a table top that was straight and inline with the anchor point. Finally, with each line gently pulled straight to begin the test, my fingers pinched each line above the end of the tape measure to mark the starting points.

With each line straight and my fingers in position, I then pulled each line separately. I applied what I felt was equally heavy force to remove as much stretch as I could without possibly damaging or breaking each line altogether. When each line was pulled to my maximum applied force, I took note of how far my front line-holding finger had traveled up the tape measure. The results?

WF5F RIO Bonefish: Stretched approximately 26 inches

WF5F RIO InTouch Gold: Stretched approximately 5 1/2 inches

That's right, my beloved Bonefish line stretched about 20 1/2 inches more than the InTouch line—that's substantial! While I wish this could have been a totally exacting test conducted in our California laboratory, I think this still proves well enough that RIO's ConnectCore is absolutely legit!

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