Rotational Moment of Tenkara Rods 4 meters and Longer

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Great data and article, Tom. Thank you very much for making this information available. It can be a real asset for the prospective rod buyers who will take the time to read it and study it enough to gain an understanding of the data presented so they can utilize the information you have provided for us. I have a few rods (or have but no longer own) some of the rods on your listing, and my experiences casting and fishing those rods with respect to rod flex indexes, perceived tip heaviness and comfort, or lack there of, in casting agree exactly with your stated findings. You have provided a great and beneficial service for all the T-anglers out there who will choose to use the information you have provided the easy way - Before putting their money down and taking their chances with a rod that sounds good on paper but is a Dog in your hand and on the water. Thank you again…Karl.

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An after thought: Tom, it would be very helpful if the pound tippet and X Ratings for each rod model listed were also added and included in your tabulation…Karl.

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I agree, but unfortunately the vast majority of the rods listed don’t have tippet ratings advertised. I can’t include data if it doesn’t exist, but I’ll add tippet rating to those that have them.

-Tom

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“a rod that looks good on paper but is a dog in your hand” is a brilliant phrase, and one I think we’ve all had a bit of experience with.

Much as I love empirical data, I treat it like a compass… it’ll provide you with a direction, but it won’t get you anywhere by itself. Whenever my (tenkara supportive) fly club has a tenkara event we’re really big on casting other peoples rods, especially for those looking to make a purchase. No substitute for the actual hands on feel.

With a data set like this, if you know the numbers for a rod you liked, you can really zoom in on what else will feel good to you, or what you didn’t like and can stay away from.

Thank you for sharing this!

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My rotational moment chart has now been updated with tippet ratings. There was more data than I thought there was! Thanks for the recommendation, Karl.

-Tom

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Tom, my hope is that the rod makers will take note of your most informative work and find it in their best interests to supply Maximum Tippet Ratings for the rods they are making. TenkaraBum supplies some information a long these lines but it is sketchy and infrequent, at best. Buyers need to step up and demand that this kind of information be supplied, as best we can.

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Here is an article Tom wrote some time back on the Swing Weight of T-Rods, but it is closely aligned with the Moment Value measurements and shows how moving your hand placement as little as an inch can relieve that Tip Heavy feeling in long rods and perceived casting effort with accumulated fatigue and resultant muscle strain as well.

This is something that you can easily demonstrate to yourself with any tenkara rod: First, cast the rod with a rod length of the line the rod calls for, holding the rod’s grip in the palm of your hand and the tip of your first finger placed on top of the grip in the valley between the 2 humps of cork. Note how heavy the rod feels in holding the rod parallel and in casting.

Second, place your first finger tip on top of the rod blank just in front of the grip, note how much lighter the rod feels in holding the rod parallel to the ground and in casting. You should be able to feel a significant difference.

Third. note how the bigger part of the back of the grip is aligned on the underside of your forearm and is easy to rest against it for much greater leverage in hooking and playing fish, whether playing then vertically (tip up) or horizontally (tip down). giving you much more control with much less effort. Try it and see what you think…Karl.

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The more I fish tenkara, the more aligned I become to it’s original engineering. This is not to discount the fun of loading up a large fish on a long 5.3 m fixed line rod. It is a ton of fun, and I feel that if you enjoy this sport you should experience it and how quickly a large fish will come to hand with that giant shock absorbing spring. I would say fish fighting and the ability to fish the opposite side of some large river boulders are a couple of key attributes.

All that said, as time goes on, I am moving more to prefer a shorter rod. I feel I can do more with a 320 length than I can with a 380 and it is more appropriate for the water I fish. It is not so much the swing weight or tip heaviness but it is more about the fidelity of control. Control over the rod, the line, and the fly.

This loss of control in longer rods is related to rotational moment and tip heaviness, but not what most imply with those attributes. This is not a strength or fatigue issue, this is a precision issue. For me it is finding the right proportion between fish fighting length and level of tip precision.

The best way to explain this is to imagine tying a paint brush to a very long stick. Then grabbing the opposite end, try to write your name, then try the same exercise with a short stick. So much of my success in tenkara is about rod tip control and how that relates to presentation. The deeper you dive into classic tenkara presentations/manipulations the more value you may find in a shorter wand.

This fish was taken on a TUSA sato, which is advertised to be a 390, but actually measures out to 380ish. I did not measure this brown but it was in the 24" class. Long rods are not necessary to land large fish. I have taken several fish in the 20" class on 320 size rods without any issues. That sized trout have always been bycatch for me. They are not my target, so I would never sacrifice presentation control for higher potential of landing the large.

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Moment is a measurement of Torque, which is measured in Foot/Pounds, which is a hard concept for anglers to wrap their minds around in relation to fishing rods. Swig Weight, on the other hand, relates very well to the Tip Heavy feeling that all long to very long rods will have - the longer the leaver, the more tip heavy the rod will feel.

But not all weight is created equal. With a fish on the line, the rod feels pleasantly tip heavy and none of us object to that feeling. Add weight to the butt of the grip, and the rod will feel much lighter at the tip end. The moment will not change because the length of the lever is not changed. Moving your grip location forward on the grip (index finger on top of the blank) moves the lever’s fulcrum forward, shortening the length of the leaver, making the rod feel much less tip heavy with the new grip location. The rod weighs the same and is the same length but, the length of the rod in front of your hand is shorter, and hence the lighter feeling rod.

In most of the photographs taken of tenkara fishermen fishing and casting, the casting hand is located at the back of the rod grip. So much so that the rear grip location has become the default casting and fishing position of choice for most anglers. I presume because it offers the maximum reach and casting range. And yet, how much more rod length does the back hand position grip really give? Not much more than a hand width, if even that. Lengthening the tippet or going to a longer line will give far more effective reach to the same rod while giving the angler a much more pleasant fishing rod to cast.

Plus, the finger on top of the rod blank will provide sensitivity comparable to what keriyu and seriyu rods offer, because you can override and exceed the lack of sensitivity that cork, foam and wood grips absorb on tenkara rods. This is a win/win situation all the way a round, simply by moving your hand up a few inches and putting your first finger on top of the rod blank. And it will also give better casting accuracy and fish fighting information as well. This grip location takes most of the pressure off of your wrist and transfers it to your much stronger elbow and shoulder muscles, if you rest the back of the rod’s grip against your fore arm. Instead of rod/wrist fish fighting, it becomes rod/elbow/shoulder strength fish fighting, with the wrist doing the steering of the fish by using tip/down side/pressure technique.