Sometimes I think that the words that we use can then to lead us astray. What we are calling vibration can actually be in either the frequency domain or the time domain. When a lure just stops what we feel can probably better be called an impulse because it is in the time domain not the frequency domain. An impulse in the time domain or a vibration in the frequency domain are equivalent or one can be mathematically converted to the other. The same is true of resonant frequency. It has a time domain equivalent. But either an impulse or a vibration can be transmitted up the line and through the rod to the fisherman's hand.

If I'm winding a lure through the water and it stops dead in its tracks, I'm pretty sure I could feel that no matter if I was using a graphite rod or a heavy iron pole. There could be no way that I wouldn't feel it. It's not like I'd be able to keep winding and not notice that everything had locked up tight and that no more headway could be made. When everything stops, you know it!

Ken;
Yes!
I've had fish stop a bait dead in its tracks, I've also had rocks, and logs, and fishing line, and many other things do the same.

I but detecting whether it’s a fish, or a rock, or something else is were sensitivity comes in.

I don't want to set the hook on the rock or log and I do want to set the hook on the fish.
Being able to tell the difference means more fish in my boat and less baits broken off in the bottom of the lake.

I agree with Tom Kirkman,the long rods are more sensitive.
I fish 100 % on the bank and 99% with jig,so i fish with 9'-16' rods using spinning reels and braid(FIRELINE 4LB.,SPIDERWIRE STEALTH 6LB.,SPIDERWIRE ULTRACAST 10LB.)+fluorocarbon leader.
I fish with so long rod for better sensivity and because i need to cast long distance and to set the hook in right time.In the same time the long rod help me to fight with big fish with tinny line and small jig.
About the weight , my 16,4 feet telescopic rod (TRIANA Special Competition GRANDSLAM VHS made in Italy by Gabriele Tubertini) weighed only 6.7ozs.I was catching on 1/8oz..jig with this rod one 23lb. red fish using Fireline 4lb. line and manny flounder.

Jean,

No doubt that longer rods make it easier for you to detect a fish on the other end, particularly on the strike or bite. But a 9' to 16' rod with that resulting heft and balance is probably not what most anglers here in the U.S. would consider as being "sensitive." Everyone seems to have a different definition for that word.

By the way, when we talk about long rods we're usually talking about 7 or 8 footers, or anything that might be a tad longer than those typically used for a certain type fishing. For what you're doing, that extremely long rod is no doubt the best thing you could have in your hands, but it's "foreign" to most of us guys here in the U.S. Our long telescoping type rods for bream fishing weigh a heck of a lot more than your 6.7 ounce model, that's for sure.

I've always been amazed at the very long rods in use throughout Europe for the fishing you do there. The selection I see in the European tackle catalogs is really astounding.

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Tom,

You right again,but i am from Europe and all my life i was fishing with long rod and i know the advantage of longer rods.

Regards,

Jean

So Tom/Jean- you are telling us that a 16' long, 6.7 oz rod- which is obviously not going to be very stiff at all, is going to be able to detect the bite of a fish better than a rod that is stiffer and weights perhaps half as much? I find that exceedingly difficult to believe given that weight and flex are two of the things that most negatively affect blank sensitivity (transmission of motion from tip to butt).

European rods are not made long because that makes them more sensitive...

I can certainly feel the fish strike better with a longer rod, regardless of the stiffness involved. The fish will hit the rod harder and move farther simply because he can.
Give him a longer lever and he'll use it against you every time. The more force he can apply against you the more you're going to notice it.

This is the problem with any sort of controlled laboratory experiment in this particular realm of "sensitivity" - in such a test we make the assumption that the fish strike or bite is going to be the same no matter how long the rod is. Not so. The shorter rod allows you to arrest the movement of the fish more easily; with less effort, so the fish can't move as far, fast or as hard as he can with a longer rod in your hands.

Going back to my earlier statement, there are many aspects of "sensitivity" and rarely are we all talking about the same aspect at the same time. For what I do a 16 foot rod would be a terrible thing for me to use. But for what Jean does it is probably not only the very best tool, but the most sensitive one as well.


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As Mike points out the two largest variables determining sensitivity are weight and stiffness.
As the length of a rod increases the weight must increase and therefore sensitivity decrease.
Also as you increase a rods length the stiffness drops at the SQUARE of length causing sensitivity to drop dramatically .
Also as you increase a rods length the mechanical advantage that the fish gains goes up but it only goes up directly with the increased length.

With all due respect Tom, that's not quite true. Emory is right on. The heavier the rod, the harder it will be for a fish to move and the more of that movement that will be absorbed/deadened by the mass. On top of that, every bit that rod flexes is a bit less movement at your hand.

The lever argument is compromised to a large degree by flex. In those lever diagrams, the planes are always shown as straight. Were you to incorporate flex into them, you would see something quite different. Now if weight and flex were equal, you would be incontrovertibly right. But they never can be, and so it just does not play out the way most people picture it.

The greater mass is so slight for the increased length that it is trumped badly, very badly, by the increased length. I'm not picturing this or offering conjecture, just what I know to be true. We'll also have some tests in a future issue of RodMaker that I think will illustrate this very well. The same size fish easily moves the longer rod farther. Easily. By the way, the increased weight actually works to the fish's favor as well in this respect - it helps him move the rod. Remember, there are different aspects to the sensivity picture and vibration is only one of them. Movement is altogether another.

I have been working off and on with a very talented tool maker and I think we have developed an apparatus that fairly well mimics what happens when a fish "hits' a lure or bait. We know what happens, movement wise at the handle, for a given input at the rod tip. There will still be some things that we haven't yet figured out how to measure, but we've got the movement down. Longer rods move farther, and harder, at the fisherman's hand than shorter rods do. Not an ounce of doubt about it. I always figured this to be the case, now we have the data to back it up. I don't want to let the cat out of the bag too soon. We have a few more things to do before we complete the article.

I do agree that many people make the mistake of thinking of a rod in the same way that they do a straight, non-flexing lever. You'll also recall that in the volume 5 #6 issue where I wrote about fishing rods being levers, I also mentioned that in actual use the effective lever length is only the distance from the fulcrum to the end (tip) of the rod in a straight and parallel line along the rod (not drawn between butt and tip) which takes into consideration rod flex under load. I've covered the aspect of flex in a lever pretty well previously, I think.

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Tom,
The same size fish will only move the TIP of the longer rod further because the longer rod is not as stiff. If enough material is added to the longer rod that the two rods of different length are of equal stiffness the increase in the mass or weight of the longer rod will not be slight as you suggest.
No offense, but I think that if you conduct your testing scientifically, controlling all of the variables, which is not going to be trivial to do, you are going to be very surprised by the results you get.
But I do agree with you that I need to spend more time on the water and less time here.

The longer rod can be just as stiff as a shorter rod. I tend to do scientific tests rather than hodge-podge types of things. I have no use for things that aren't well done or controlled to the point that the data isn't actually useful. That would just be a tremendous waste of time.

Everything that you and Mike have said in this thread mirrors exactly what I have been telling people for many, many, many years, at least insofar as vibrations are concerned. But that's not at all what I'm talking about with regard to this aspect of sensivity. That information is still valid, but it's not being applied correctly to the aspect at hand.

I wasn't surprised by the results (we already have them).

And again, the heavier rod will be easier for the fish to move. Much easier. Stay tuned.

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How is saying a fish can move a heavier rod more easily than a light rod any different than saying it's easier to move a medicine ball than a beach ball? Or are you using the word heavier to mean rod action (as opposed to mass)?
?