I guess we can agree to disagree. Maybe my interpretation of “sensitivity” is not quite the same as Tom’s. I subscribe to Mike Naylor’s and Emory Harry’s positions on the subject in this thread this thread from 2007

[www.rodbuilding.org]

"Sensitivity" is like a deity: It can't be seen, felt, heard, or measured, but it must exist.

Jim,

I think you misunderstood the intent of the article. The article does not contain my interpretation of "sensitivity." Rather it was intended to show that the term means different things to different fishermen and therefore rod builders need to understand exactly what it is that their customers are after when they speak about sensitivity.

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Tom, I agree, some do have different interpretations of sensitivity.

I guess where I disagree is where you stated “ I’ve long known that longer rods allow you feel a fish strike better, precisely because you’re handing the fish a longer lever to use against you”.

In regards to line or rod movement …..if a “bite” occurs resulting in a line movement of 1 ½” and assuming the tip of a 7 ½’ rod (w/braided line) moves the same amount (1 ½”), a 5 ½’ rod would move about 3/16” less. This “disadvantage” would be negated by the lighter (less mass) of the shorter rod. Assuming of course, that both rods were of equal power and stiffness. Consider no rod at all……if the line was held in hand, resistance would be felt immediately, with very little pull of the fish or line movement…..even though the fish has no leverage advantage.

The great majority of fishermen fish with bait. For them the advent of circle hooks makes rod "sensitivity" unimportant, no matter how you define or measure sensitivity. Bait anglers using circle hooks do best by leaving their rod in the holder and letting the fish hook itself. Don't pick up the rod until it is bouncing all over the place. This will increase your bite to hook-up success by at least 30%, end "gut-hooked" fish, and lower the mortality rate of little fish released to grow up. Those eye-popping, full-strength hook-sets by 240 pound anglers on two-pound fish are just advertising gimmicks.

The load times its distance from the fulcrum is equal to the effort times its distance from the fulcrum.

If you go out and try it, with two different length rods, you'll see that the longer rod is exactly as I stated - the fish can apply more pressure against you because he has a longer lever. You will feel and/or experience a lot more force from the same fish action (whatever it is). However, this is not to infer that the longer rod is necessarily more "sensitive." Different things and back to the point of the article.

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Yes, leverage with longer rod gives a fish an indisputable mechanical advantage, and it is apparent when fighting a fish. But, I don’t think “leverage” is much of an issue regarding sensitivity with bite detection or lure activity. I think in terms of a “bite” (or lure movement) transmitting a “signal” up the line to the angler’s hand. Any rod (regardless of length) and the reel only acts to degrade this signal…..not enhance it. A shorter, lighter rod of comparable power/stiffness (to a longer rod) should be less inhibiting. There are conditions that allow the angler to run the line over his/her finger, negating the “signal loss” incurred thru the reel between the line and rod, but some retrieve methods make this impractical.

There really is no "signal" to be transmitted - it's not an electrical current. Some years ago we did some tests in a swimming pool, with anglers blindfolded, retrieving a plastic worm through the pool. Another angler would stand in the pool and slap the worm as it passed by. Not a single angler was ever able to detect the slap. The only time an angler felt a "bite" was when the person in the pool actually stopped the worm, even momentarily.

You can take this further by testing with two rods, one shorter and one longer, but both with the same relative power and action, and pulling a large bladed spinnerbait through the water. The longer rod will generate much harder vibrations at your hand than the shorter rod will.

Beyond rod length and all else being equal, a higher stiffness to weight ratio will result in a more "sensitive" rod, but then we go back to the point of the article - different people mean different things by sensitivity.

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The only thing you are ever going to feel on a fishing rod is resistance. Unless something is pulling on the line like a lure or a fish, nothing else is going to happen that you can feel. And the line has be under tension for anything like this to happen. I understand the point of the article was not to try and define the term sensitivity and agree that fishermen all have their own subjective opinion on just what it is.



Edited 1 time(s). Last edit at 02/01/2020 05:26PM by Mike Ballard.

In spite of my reluctance to believe leverage plays much of a role in “my” version of “sensitivity”, and in an effort to keep an open mind, I conducted the test Tom suggested…..or at least similar. I figured that rather than using two different rod lengths, I could replicate length differences by simply changing the angle of the rod….the rod at 90 degrees to the retrieve obviously representing the longer rod. Gradually pointing toward the retrieved lure would effectively shorten the rod.

This being a purely subjective test(s), I had to try with different type of lures. I began with chatter bait, which I thought the vibration was too extreme to make conclusive comparisons. After trying several “action” type lures, I tied on a spinnerbait (Indiana blade) with a more subtle vibration, which allowed me to better discern vibration variations at different rod “lengths”. As I said, this is all subjective, and I’m reluctant to share my conclusions, but I’m inclined to stand by my previous posts.

The biggest surprise came when I pointed the rod tip at the retrieved lure, negating the rod length altogether. I had to make multiple casts to ensure my conclusion.

I encourage anyone who might consider “sensitivity” to be important, to try Tom’s test for themselves…..including a retrieve with rod tip pointed toward lure.

I tried doing this test in my driveway, but the results seemed inconclusive. Dragging a test weight over concrete or blacktop just felt rough and lacked a discernible modulation (for lack of a better word) between variations of rod lengths.

No, you need to actually change rod lengths. Simply changing the angle of pull does not create a longer lever.

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I considered using the 2nd or 3rd guide from the rod (same rod) as the tip-top to replicate a “short rod”, but my “test” results enabled me to draw my own conclusions without any further testing or theories or mathematical calculations. I’m pretty well convinced that the rod inhibits rather than enhances sensitivity, so the lightest (least mass), stiffest rod is the lesser of the evils. Btw, I had my wife perform the same test and gave her none of my expectations so that she wouldn’t be biased. She had no idea what outcome I had in mind. Her impressions were that when rod was at 90 degrees, she felt more resistance, but when tip was straight out, she felt vibrations much more readily. Sensitivity decreased as the rod moved toward 90 degrees, while resistance increased (as the "lever" became relevant).

Here are a couple of relevant paraphrased posts from the past:
From Mike Naylor:
[www.rodbuilding.org]
“The assertion that longer rods are more sensitive if all things are equal; they are not equal. Stiffness is inversely proportional to length SQUARED. So a little increase in length results in a significant decrease in stiffness. To maintain the stiffness, a significant amount of added material (and therefore mass) will have to be added. This is why longer rods begin to feel tip-heavy.
In practice, longer rods must have more mass, a steeper taper, or a stiffer fiber to achieve the same stiffness as a shorter rod. A blank designer could increase the modulus or the diameter of the longer rod to make it stiffer. But then again, all things are not equal.

Given this, in practice you will find that a shorter rod is going to feel more sensitive because it will be lighter and it will be stiffer than a similar rod that is longer.
And don't confuse how hard a fish can pull during a fight with how sensitive a rod is. A twelve foot long rod would make any fish feel big, but it would not be a sensitive rod.”

From Emory Harry (regarding interpretation of “sensitivity”):
[www.rodbuilding.org]
“Rod sensitivity shouldn’t become a question of semantics. If it does, then attempting to quantify it or measure it or determining the variables that affect it or attempting to compare one rod to another all become a waste of time.

I define sensitivity as the amount of the energy in the fish's bite that gets to the fisherman's hand. I did this in an attempt to remove as much subjectivity as possible but I will admit that this definition is not perfect. However, I do not think that we should make it a word game.”

While others might disagree as to what sensitivity means, it would be prudent to ascertain what is meant or desired.



Edited 1 time(s). Last edit at 02/03/2020 07:48AM by jim spooner.

The load times its distance from the fulcrum is equal to the effort times its distance from the fulcrum isn't a theory - It's a physical law.

Try your test again with two rods of similar power and action but one longer than the other and you will find the result will be as I have stated.

And again, the article in no way attempted to define "sensitivity" nor to suggest what would make one rod more sensitive than another. It simply pointed out that when a fisherman, a potential customer, begins talking about "sensitivity" you had better find out what he means by that term as it may be something entirely different than what you think of in terms of sensitivity.

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Did that this AM, same conclusions…..although the longer rod did offer more resistance at 90 degrees to lure retrieve . If I had two rods that varied more than 18 to 24” in length, it’d be easier to say objectively that one was much more sensitive than the other.

I can only suggest to anyone that they try test casting with different rod orientations as I have stated. It’s pretty easy to make one or two long casts with any rod, regardless of length. Using a spinner bait, simply make a long cast and while retrieving, hold the rod 90 degrees, then gradually point the rod tip toward the lure during the retrieve to determine which gives you a better vibration. You might be surprised at which hand you feel it in. I think the test will disavow any notion that a rod enhances sensitivity. Resistance/load is evidently not the same as sensitivity.

It might be worth considering how we orient the rod during certain techniques where sensitivity is a desirable trait.

My focus in on the end result, so beyond that, I leave it to someone smarter than I to reverse engineer and provide applicable formulas to explain the physical law.

Since most anglers choose rod length for reasons other than sensitivity, it might be a moot point anyway. I prefer shorter rods for other attributes, but the increased sensitivity is an added bonus.

Btw, I never asserted that the article tried to define “sensitivity”, or took exception to any of the rest of it other than the “longer rod being more sensitive”. And as I said in my last post: “While others might disagree as to what sensitivity means, it would be prudent to ascertain what is meant or desired”.

I also said initially we can agree to disagree on whether long or short rods are more sensitive. I hope I'm not coming across as belligerent.



Edited 1 time(s). Last edit at 02/05/2020 11:03AM by jim spooner.

Jim,
I will say that one of the most sensitive rod that I own is an 18 inch long ice rod.

I will also say that I have a 10 foot noodle rod that is very very good at detecting a bite, due to its very soft tip. Of course, in the case of the 10 foot noodle rod the sensitivity is primarily due to the visual action of the very soft rod tip on a bite, and not what is actually felt in the hands of the person holding the rod.

So, again - what is the definition of sensitivity.

I liberally use the word sensitivity in the fishing world to relate to putting more fish on the boat - compared to another rod. If one rod is more sensitive - either due to feel or sight, then it puts more fish in the boat for me.

Also, a technique commonly used by folks fishing for extremely light biting fish is to grasp the fishing line between a couple of fingers. Then, the line is the main transmission of the bit of a fish that is transmitted to the finger tips and not necessarily anything to do with the rod blank.

Be safe

To me, sensitivity is the feedback transmitted back through the line, guides, and blank. The lighter the blank the greater the sensitivity. My big heavy action rods require something more pronounced to feel a feedback.

The sensitivity is transmitted in the form of micro-vibrations.

My rods that are under 4oz, if I use braid or flourocarbon line (little to no stretch) with a dense weight like tungsten, I can feel the texture of concrete, rocks, tree branch, sandy bottom, clay bottom, muddy bottom. I can feel when the bass picks up the bait and drops it.

To me this is sensitivity.

I have a theory the semi-micro or micro guides do a better job at creating these vibrations due to the line being closer to the blank. Also using a reel with a body that is made from a metal like aluminum or magnesium helps greatly my reels made with carbon dampen these vibrations to my hand.



Edited 1 time(s). Last edit at 02/04/2020 11:29AM by Jason Yu.

The difference in stretch between FC and braid is major, the difference between FC and mono is minor. At very low forces stretch may not have a lot to do with "sensitivity," and the more direct line path to a lure fished on the bottom with FC probably contributes to better feeling of the "bite."

So a fisherman comes to you and says to make him a rod that will be sensitive in a rod holder. He will not be holding the rod. How would do it?

Hello Mike.

The only way to do that is to sight fish which means VEEEERRRRYYYY soft tip.



Tight Wraps & Tighter Lines.

Bob,

New Bern, NC.

In which case sensitivity becomes more about being able to see a strike rather than being able to feel it. Which was sort of the point of the article.

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