Line strength, drag setting and rod’s rating

Line strength, Drag Setting and Rod rating


A couple of people had asked me questions revolving around these few topics and each time, I took the time to explain it till I’m getting bored with repeating myself, so I decided to put these down in words at my blog so anyone who asks in future will be directed here.

Rod Rating:
How strong is a rod that’s rated 8-14lb? How do I know if it’s ok for my style of fishing? What rod should I pair with this reel that I have? These are some examples of the questions I get. And the best one was not a question but a statement — This 140 lb guy said to me: I’m gonna get that 8′ PE6-8 popping rod. I was amazed and asked him “are you sure”? But let’s start from the beginning.

Since there are no industry wide standardisation of ratings for rods, fishing rods are often rated by the manufacturer’s marketing department, some state their line size range while others are rated by their drag range. Some even have casting weight ranges included. So I’ll attempt to put this mish mash of information into simple practical terms.

Line Rating:

At 0.29mm (3号) diameter and 30lbs rating, Sufix 832, a trusted line amongst heavy cover anglers seem to confirm the saying that 1号 = 10lbs

How strong is Gelspun Polyethylene line, commonly called PE line by the Japanese? Here is where tradition and marketing hype all play a role in muddying the water for an angler. American brands rate their lines by poundage, while European brands tend to give a line diameter and breaking strength*. In the old days of nylon monofilament line, this poundage was the breaking strain of the line. Meaning, that the line should break at or below the stated breaking strain, as IGFA standards are based on the maxim of catching the largest fish on the thinnest line.

Then when Spectra and Dyneema made it’s debut, they found that these superlines could hang an incredible amount of load for an extremely thin strand of fibres and yet not break! Everybody switched to Braided Lines/Superlines/Gelspun Lines/PE Lines (depending on where you are, you called it differently although it is the same). But soon, came complaints of lines bursting below its rating. It was later found that these lines did not underperform, but because they have very little stretch, the line will break below it’s rating if shock loaded. Manufacturers started to under-rate their braided lines to stay safe from litigation, and so you can have 10lb rated Fireline which can pull the scales to 20+ lbs**!

On the other side of the pond, the Japanese were also making their own superlines which they call PE line after the raw material that these lines are drawn from. The Japanese used their line ratings from a standard adopted by the Toyo Rayon Company (Today known as Toray) for calculating silk. In days of yore, a Standard Length (150cm) of silk line with a weight of 1 Rin (厘) 0.0375g has a diameter of 0.165mm and is called 1号. Toray continued using that standard when they produced Nylon lines where 1号 nylon monofilament has a diameter of 0.165mm. The widely accepted conversion of breaking strain to 1号 is 2kg for Nylon and 5.5kg for PE lines***  That’s how our anglers simplify it to mean a PE1号 = 10lbs.

This however cannot be the basis on determining breaking strain of a line, as improvements in coating and weaving methods have increased it’s breaking strain. In the picture above, Super Fireline has an Issue Number of 1.5号 but a breaking strain of 10.9kg! An increase in strength of 2.9kg (6.4lbs)!  As you will see later, it is therefore important to the angler to know the breaking strain of the line when setting drag tension.

Using the appropriate line/drag poundage:
If a fishing rod has a rating like Fast, 6-12lb, lure: 1/8-5/16 oz, does it mean the rod will break if you use line above 12lb or a lure above 5/16 oz? The short answer is yes and no.

I’ve seen rods break even though line weaker than the max rated strain is used. I’ve also seen lures exceeding the max rated lure weight being casted to no apparent detriment to the rod. But I’ve never seen a rod cast a lure well if the lure is below its minimum lure weight rating.

So my personal thoughts for this is: Work within the recommended limits and if you try to push beyond, you ought to know what you’re doing and be prepared for breakage.

For our example of a 6-12lb rod, I take the middle number between the extremes to be the best rating. In this case, the middle number between 6-12lb is 9lb. So to use this rod to its optimal rating, I’d use a 9lb line and set the drag at 3lbs (I’ll come to drag setting later). This will give the rod a good bend and yet stay safely within the rating when loaded and the line from the tip is at an obtuse angle to the rod. Now with this knowledge, you can apply it to other rods and stay within the rating while making the most out of that rod’s strength without fearing breakage.

Storm here gives a Medium Light rating to the rod as well as a 6-12lbs line rating and 7-15g casting weight

There is also another form of rod rating. It is descriptive eg ML which stands for Medium Light, MH or Medium Heavy etc. although it is descriptive, it is not useful in calculating the line poundage you can use to maximise your rod, so I normally only use these terms when talking and describing a rod, eg “he used a Medium Heavy Fast action rod to fish for groupers” but not when calculating appropriate line strain.

Choosing the most appropriate action:
Next comes the action. This can be a very confusing thing to a novice who had not the chance to try fishing all kinds of rods. I liken it to describing the handling of a pair of tyres – unless you have driven many miles in that seat until you are intimately familiar with the car’s every response to your inputs of gas, speed, traction and steering, the handling of one tyre feels as similar as the other.

So to assist the novice, we look at the application of an action to a particular style of fishing.

An Extra Fast action rod has a very short flexible tip while the rest of the rod resists bending. This style of rod is best used for top water lures as the Ex Fast action helps give better life to poppers and Walk The Dog types of lures. It also is great for drop shot where making tiny lure movements require a rod with less flex. If your lure needs twitching, an Ex Fast action rod will make it easiest to achieve the darting response you seek. Ex Fast action is also great for fishing snags. You feel the fish tap, you strike and fish is yanked out even before it has chance to dash back home since the rod flexes little. But because the rod does not bend much, it has the tendency to straighten trebles and split rings unless these are upsized. The stiffness also could tear a thin lipped fish or cause the hole in the mouth to widen, and in a jump, the hook can fall out as there’s less tension on a line when a rod is only slightly bent.

Fast Action rods are more common than Ex Fast action. Here, the flexible tip bends a little further down than an Ex Fast action. Fast Action rods can competently do all that an Ex Fast rod can do. The Fast Action rod develops more of a bend before the stiffer body of the rod takes over to muscle in the fish. This bend helps absorb shock better resulting in fewer pulled or straightened hooks. Fast action rods are excellent for lure fishing, or baiting at places with snags.

Medium Action rods have a flex right down to almost half the rod length. These are general purpose rods that are used mainly for baiting. Medium Action rods tend to hold a fish better than a Fast Action because its large bend helps keep tension on the fish and also absorb shock. For the same reason, Medium Action rods are also great for Eging (jigging for squid and cuttlefish using a lure). And Medium Action is great for working crankbaits – you can feel the lure bump the bottom, but a flexible tip is more forgiving in not causing the lure to be irretrievably snagged. A Medium Action rod exerts less leverage on an angler than would a Fast or Ex Fast action.

Slow or Parabolic Action rods will bend from tip to the handle, creating the biggest bend of all the actions. Parabolic rods are best for fishing very light lines, or if the fish have very soft mouth which tear easily in the fight, or a fish that tends to jump and make fast changes of direction. The big curve of a parabolic rod is able to absorb shock and keep constant tension on the line better than a Medium Action Rod can, and it exerts the lowest leverage on the angler – great if the angler is light in weight and attempting to tackle large fish. A Noodle rod is an extreme version of this action. It is so ready to flex that some rods will already bend by its own weight when held parallel to the ground. These are dreadfully lethal on fast and jumpy species such as Garfish and Giant Herrings, where the conversion rate from hookup to landing is a lot better than that when using an Ex Fast Action.

Compound Taper rods have a flexible tip that allow you to impart life to your lure or jig, but when a fish is on the line, the blank loads up and bends in a neat, contiguous curve. These rods are the result of talented cutting of the graphite sheet and naturally comes with a nice price tag to match.

Casting weights and different blank design:

Lure casting rods have relatively lower lure weights to their line rating as the lure need to be whipped through the air. 

Jigging rods have a high lure weight capability. However, these are meant for jigs that are dropped overboard and not for casting. If you should cast a 100g jig on this ABU Salty Stage rod, it is highly likely you will break the rod.

When I started fishing, I used to think that if I need to cast further, I needed a longer rod. If I needed to use a thicker line strain, I needed a fatter rod and if I needed to cast a light lure, I needed a softer rod. Technology has changed this somewhat. But one just can’t totally defy the laws of physics all the time, so the basic principles still holds true.

To cast beyond the surf, a long surf casting rod that’s capable of punching out a 4oz lead weight is still required. And to do battle with 1000lb Marlin, a fat, parabolic rod in the fighting chair is still de rigueur.

But to cast a tiny light lure, blank builders have developed a soft solid tip set into a Fast Action, blank with compound taper, so now, a Medium Light 6-12lb rod can be capable of casting lures as light as 2g (5/64 oz) up to 18g (41/64 oz)! Also, rods with Titanium composite nibble tips have opened new possibilities in having a soft sensitive tip to fish for cautious fishes, yet having enough grunt to handle a heavy sinker.

Setting the drag:
We now know how to determine the amount of drag a rod can comfortably handle. The next step is to set the drag on the reel. But before we do this, I should explain why I said to use a “9lb line and set the drag at 3lbs” earlier.

Firstly, we must realise that drags are not constant throughout. A 3lb drag when the spool is full to the brim may become 4.5lb after you had cut off a bunch of line as the result of a professional overrun and the further down the spool you go, the heavier this drag setting becomes.

Secondly, line loses its strength at the knots. Thirdly, line loses its strength from UV damage, water absorption, and from microscopic nicks and scratches during use.

So to insure against breakage, we’d set the maximum drag at half the line’s rated strength, and because the drag increases as line is run down, set the initial drag at strike to a third of the rated line strength. In order to do this, you need a spring balance and a helper.

Fix reel to rod, thread line through all the guides and tie line to the spring balance. Have your helper pull the spring balance, until line spills out of the reel and the rod is loaded up. Note the weight recorded on the spring scale and adjust accordingly. Because friction of line against the guides also influences drag setting, you shouldn’t set your drag without first running the line through the guides and loading up the rod.

With drag set up this way, you can be assured that you are using the heaviest pressure possible with rod and line, to subdue the fish with the least possibility of breaking rod or line. However, do remember that when you fight the fish, you should be keeping the line in as obtuse an angle to the rod as possible. If the line is at less than 90° to the rod (happens when you high-stick when fish is near), you run the risk of breaking your rod even though your drag is set correctly.

Moments after High-sticking this rod, the fish made a dash for the bottom and snapped the tip.

Pairing rod and reel:
When pairing the reel and rod, we need to take into consideration, the rod’s line rating to calculate drag, and also to understand the purpose of the rod.

If a rod’s ideal line rating is 9lb, then selecting a reel that’s capable of 4.5lb maximum drag will give you the lightest possible gear to do the job adequately. Remember that if you are holding the rod in your hand all day long, having something that’s too heavy will be less enjoyable than holding something light. Get a reel that loads sufficient line for your purpose and has adequate drag. Don’t get caught up with the numbers chase. Instead you will enjoy it more if you use the lowest that you can reasonably use to land the targeted fish.

However, if you used a line is under-rated (a 10lb line that breaks at 20+lbs), caught a world record-sized fish and submitted it to IGFA to claim your record, you may be disappointed when you find that your line’s under-rated strain cause your entry to be disqualified.

If you are casting a lure or holding the rod in your hand for an extended time, you also want to get a balanced set. With reel fixed to the rod, hold on the foregrip. The rod’s point of balance should be found here or better still, closer to the reel. Having a balanced set can relieve a lot of fatigue and it’s possible to modify your rod with some counter-balancing weights to bring the centre of gravity closer in towards you. But that will be dealt with in a future piece if there’s enough people asking for it.

Is there an end to the limits?
Despite advances in technology and material, we are limited by our mortal limits of strength and endurance. What’s wrong with that 140lb guy wanting to get that 8 foot PE 6-8 popping rod? He surely need a long, fast taper rod to hurl the popper a good distance to the reef side without spooking off the fish, so the length is needed. And to muscle big GT from cutting him off at the reef, he’ll need a strong drag to stop it. And those who fish these brutes will tell you how these fish can pull a heavy drag all day long, so a PE 7 is de rigueur.

It all seems correct until you take into account the chap’s size. We may imagine we can pull heavy loads. However, we can only pull a tiny fraction of our weight comfortably with our arms. If that was not so, we’d all be able to do chinups all day long for as many reps as is required. But the opposite is often true and in most cases and it’s common to see people thrutch and kick their way to get that one chinup count.

So let’s do our sums as a revision of what we have learned so rar. The PE 6-8 popping rod’s ideal line is PE 7 or approximately 70lbs. You would set strike drag at a third of this which is 24lbs. Now it’s quite reasonable for a 140lb guy to pull 24lbs with his arms. But don’t forget, he is pulling it against a 8ft lever that’s set up to work against him. When faced with these odds, adrenaline can only sustain the angler for so long. The question is, how long before his excitement turns into agony?






©Lawrence Lee
All Rights Reserved
If you want to use any content for your own publication/web/blog, please write me @


7 responses to “Line strength, drag setting and rod’s rating

    • QB, because this article was written for novices, it was written in a very general nature, and not meant to cover every aspect of fishing, some of which can be rather extreme.

      For example, the current rage in Japanese Slow Pitch Jerk style of fishing will have anglers tackling deep, bottom dwelling fish such as 80lb groupers with ultra light line as PE 1.5 on an oversized reel such as a Mamiya Marfix or an Accurate BX500, screwed down to a thin, skinny, high modulus rod. To people who are used to chunking or trolling, this will sound like a ludicrous proposition to fish with such unbalanced tackle. But to practitioners of Slow Pitch Jerk, it’s the kind of tackle setup perfect for that technique.

      Another extreme example will be for those casting for the Papuan Black Bass from a small dugout canoe. A reel capable of 20kg drag is preferred or you’d need several layers of elastic plaster to cover your thumb in order to stop the fish from charging back into its lair. 80-100lb braid is par for the course, but you need a light rod to flick that 25g lure or stick bait or skip that soft plastic into the edge of the mangrove roots. Such an unbalanced setup will be most uncomfortable to fish with on normal cases, but it’s a necessity for that style of fishing.

      As for a 60kg guy wanting to pop for GT, I’d recommend him to first borrow a setup from his friends and try it out for a day of heavy popping at the beach. After that, depending on his motivation, make appropriate plans — if he still want to pop for GT, he then can go get that 8-foot PE8 rod, and also a gym membership with a dedicated trainer to help him get the strength and endurance to play this game. He may even need to hire a personal Nutritionist to help him gain a few more pounds to hold down the fish against such leverage, or wear a ballast jacket made by hanging bottles of water to his lifevest just to increase his weight.

      Or he can be realistic, and do light popping, or he can bait or troll for GT, in which case, he will be comfortably capable of catching the fish without the additional efforts needed when popping for them.



  1. Hi,

    I’m just wondering what model rod you have in the photo above the fast action section, and below the ex-fast action section. Looks like an NRX. I like the action…


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s