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Line Ratings - True or False

by Gus Mansour

More of a query than anything else. Are we all using line that is too strong for our rods?

I was reading about Honryu fishing on a Japanese website, Google translate is wonderful if eccentric, and came across a conversion formula from Line size to lbs breaking strain. They were of the opinion that the correct strength could be calculated by multiplying the Japanese size by 4. So a rod rated for a number 1 line was suitable for 4lb test tippet.

By diameter a Japanese number 1 is 4x but you would be hard pressed to find 4x that was only 4lb test in Europe or the US. Chris seems to agree with the strength conversion as he wrote on the Kyogi page that the 3 line rating meant it could cope with a maximum of 12lb line.
Esoteric tackle over here sells the Fujino Turbo tippet in size 1.2 – the maximum for most tenkara rods and they give a breaking strain of around 4.5lb.

So again are we all using line that is too strong for our rods? More importantly, am I going to break my beloved Soyakaze by using 3 lb tippet instead of the (roughly) 2 lb 7oz that a .6 rating should convert to.
At this point I wish I could afford to buy a whole bunch of rods and actually test how much pressure they took before they failed.

Personally, I would appreciate standardised strength ratings for JP and x sizes. There is a very wide variation in the actual specifications of tippet. 5X should be 0.8JP or 0.148mm. I have seen tippet rated 5X with claimed diameters ranging from 0.14 – 0.17 and strengths from 2lb to just over 6lbs. I definitely feel that manufacturers of fixed line rods should list the rods capability based on line strength rather than diameter.

Thoughts anyone?

Comments for Line Ratings - True or False

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Oct 13, 2019
Diameters / Line Strength / Rod Ratings
by: Chris Stewart

Some random thoughts:
The 4 to 1 conversion works for most spinning line but not for tippet, most of which is stronger for a given diameter than most spinning line. Even within Japanese lines, different size 1 lines have different strengths. Size 1 Varivas tippet is 5.1 lb. Size 1 Varivas Bait Finess Nylon BFS line is 5 lb. Size 1 Varivas Bush Trail spinning line is 4 lb.

Some Japanese manufacturers do not give tippet ratings. I suspect the reason for that is they are well aware that if they publish a rating low enough that they are confident the line will always break before the rod, people will think the rod is weak and won't buy it, and if they publish a standard strength, buyers will complain that their rod should not have broken and demand free replacement parts.

I have come to the belief that line ratings are suggestions, not guarantees, and are more along the idea of "these tippet strengths are what most anglers would use with this rod."

After having sold rods and replacement parts for years and years now, I am absolutely sure that following the maximum tippet rating DOES NOT mean the line will always break before the rod does. With poor rod handling techniques, you can be pretty sure the rod will indeed break before the line does.

Poor rod handling techniques include:
1. Trying to free a snag by whipping the rod.
2. Trying to free a snag by pulling the rod all the way to one side, putting a big bend in the rod.
3. Pulling back on the rod, like pulling back on the reins of a horse to try to stop a large fish from running.
4. Setting the hook like you would with a fly rod or even worse, like a pro bass angler. If you are setting the hook on a rock or log, a hard hook set WILL break the rod - possibly in multiple places. I think the record is three broken sections and a permanently jammed tip.
5. Trying to land a fish that is much, much larger than the rod was designed for. I know a guy who can and does catch huge fish with tenkara rods. I unfortunately also know guys who break rods on much smaller fish. Experience matters. Experience comes from breaking rods.
6. Whacking the rod on a tree branch while casting or setting the hook.
7. Getting your fly snagged at the extreme end of your back cast and powering through the forward cast without realizing there is additional tension on the line. (Start your forward cast slowly, to feel the line being pulled, then accelerate).

This list is not exhaustive. I am sure people can find other ways to break rods while using the recommended tippet strength.

Very rough rule of thumb. If fish NEVER break your tippet, your tippet is probably too strong.

Oct 13, 2019
One more way
by: Gus Mansour

8) Walking through scrub with your rod collapsed and not noticing that the line has caught on a twig.

I pulled the no1 section right out of the no2 which was split in the process. I'm much more careful now!

You make some good points Chris. Variations in ratio of diameter to strength and commercial realities probably make it difficult to publish accurate strength ratings.

By the way, how do you find time to stay this on top of your website and still ship packages so fast. Colour me impressed.

Oct 13, 2019
Another complicating item
by: Mike Schelp

In the US, lines are rated by "line test", meaning the given line will NOT break until the test is exceeded. For example, an 8 lb TEST line will break at OVER 8 pounds. It might be 8, but it might be 10 or 12. Typical American Bass or Catfish anglers want the strongest line possible for the diameter, and "test" fills that requirement. Once upon a time (maybe even now), there was what was called line CLASS. In CLASS lines, the line was supposed to break at or UNDER the class. Using my 8 lb example, an 8 pound CLASS line would break BEFORE it hit 8 pounds. This was the standard for works record fishing. Obviously, catching an 8 pound Rainbow on line that breaks AT 4 pounds would be different than what caught on line that breaks at 6 pounds but was "4 lb test". I flirted with doing ultralight, world record fishing many years ago, and had difficulty finding "class" line. Then again, I could be totally wrong about all of this. ;)

Oct 13, 2019
by: Chris Stewart

Mike, you are correct. It is hard to find class lines (also referred to as IGFA class lines) but they do exist. You are also correct that many anglers (and not just bass and catfish anglers) want the strongest possible line.

The problem with that thinking, though, is that manufacturers, who want to advertise very strong line, will package a line that they know breaks at 10 lb, or more, in a box that is plainly labeled 8 lb line. Consumers have no way of knowing how strong the line really is.

I may be in a minority, but I would prefer it if the box didn't lie. If I wanted 10 lb line, I'd buy 10 lb line.

Not being able to trust the packaging is a particular problem for fixed line anglers, who need the tippet to be the weak link. I frequently tell people not to shop around for the strongest 5X tippet, as that defeats the purpose.

Just today a guy wrote in asking me if there was a flaw in his technique because he broke his rod using tippet that was within the manufacturer's recommendation. I used to carry that tippet because that's what was recommended. I now think it is too strong, don't have any more in stock and will not reorder.

Again, I think tenkara rod manufacturers' tippet recommendations are what Japanese anglers generally use with the rod to catch the 9" fish that they catch. Japanese anglers don't beak rods on 9" fish. I do not believe the tippet ratings are a statement of the tippet strength that will break before the rod does.

Oct 15, 2019
global line rating standards compared
by: David

The yoz-ami website (YGK line) used to have a very informative English language page that compared line rating standards used in Japan vs USA vs Europe. But unfortunately the web page was taken down a few years ago.

The Japanese line rating system is based on line diameter. Sort of - the gou (号) number is really generated by the ratios of the cross section area of the line. iow, based on ratios - a 2号 line will have 2x the cross section area of a 1号 line. A 4号 line will have 4x the cross section area of a 1号 line. 5x line will have 0.8x the cross section area of 1号 line = 4x, and so on.

From what I've read the only standard is for 1号 nylon line. All other lines sizes are just kind of on the honor system to adhere to the cross section area ratio system as close as manufacturing quality control permits. And they use pound-class (kilogram-class) rating (lbC). Not pound-test (lbT) a tensile rating as is more common in USA.

Maybe this website will help a little bit. (though it isn't as comprehensive as the old YGK/yoz-ami webpage).

Do a Google search for anglers secrets fishing line confusion

They summarize different rating systems. Some companies use a rating for average pounds or maximum pounds or some even provide a rating based on knot strength (a knot is weakest point). Giving an example that a 10lbC line can equal a 6lbT line.

Oct 15, 2019
by: Mike Schelp

Chris, if you are in a minority wanting the line in the box to be what is advertised on the box, you aren’t alone as I’ve been in that group for 40 years. IGFA class line has become less available, if anything. The move to fluorocarbon lines, copolymer, braided line and the like has only muddied things up...and given anglers some amazing tools for catching fish. Still, I’d prefer my 2 lb line on my microlight spinning rod be 2 pound, not 4.

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