I recently ordered both size 4 Fuji KT running guides and size 4 Fuji L running guides in preparation for a build I am currently working on. The model KT is the official KR Concept running guide, while the model L is the running guide designed for the original Fuji Concept system. Looking at the two size 4 guides side by side, a few things stood out. The KTs look bulkier and heavier, with thicker frames and shorter feet. The L's single-leg frames look slimmer overall, and their feet are a bit longer. My instinct told me the KT's would be heavier. I fired up and calibrated my jewelers balance to weigh sets of each. My instinct proved accurate.

Set of 7 Fuji size 4 KT running guides: 0.536 grams (77 milligrams per guide)
Set of 7 Fuji size 4 L running guides: 0.403 grams (58 milligrams per guide)

The weight savings that comes from using model Ls was bigger than I expected. It turns out that size 4 Ls weigh about 25 percent less than size 4 KTs.

Last year I ordered a set of Fuji Torzites. I no longer have the weights of each guide in the set, nor do I have the guides themselves (I talked myself out of using them, and returned them). I do remember that, size-for-size, the Torzite rings with titanium frames weighed about 30 percent less than the identical Alconite model with a stainless steel frame. It looks to me like switching from KT running guides to Ls, at least in size 4, reduces weight about as much as using a Torzite KT running guide. The Alconite Ls are marginally cheaper than the Alconite KTs, and less than a third the cost of similar sized Torzites.

I noted a few other benefits of the Ls over the KT running guides:

With longer feet, the Ls are easier to wrap
With a single leg leading from the ring to the foot, it is easier to do a locking wrap on the Ls than on the KTs
The Ls have some texture on the top of the foot, which gives me confidence that the finish will grab them and hold

With all of that, I wonder why Fuji would design and market a running guide for their KR Concept System that is heavier than the running guide they manufacture for their older Concept system? I used the old Concept Ls on dozens of rods before the KR Concept system was developed, and never had any problems with them, durability wise.

By the way, anyone want 7 size 4 Alconite KTs in corrosion-control grey finish? I will not be using them, and my return window has passed.

Good stuff Eric..I never cared for the K guides..They look silly..Companies have to keep comming out with something new though not always improved.

To be clear, I quite like the KR Concept reduction train. My standard reduction guides are a 16H, 8M, and 5.5L. That reduction train seems to work pretty well for the light and ultralight rods I build. I am just questioning the running guides Fuji markets in their KR system.

Eric, for my lite stuff with braid I use a#8Y guide on the butt and go straight to runners..it,s a much liter guide train but only for braid..The 8 is tall enough to not get rod slap.

I think the K series has a place but for me they are FAR to heavy as you have pointed out. It is always nice to see people doing real world test such as these without needing other’s opinions. Great job keep it up!!

From my own research on the KR concept, I read that the KT guides are designed to be more tangle free with a flatter guide angle and foot shape that allows wind knots to slip off more readily.
Whether this is really the case or not, I don't know, but it is one of the reasons I looked into them and have used them. The video Fuji showed simulating these features was interesting....and like with all advertising, consumed with liberal amounts of salt.

This is most likely the reason the KT's are heavier than the L frames, as you noticed.

I have used lots of #4 L frames, and they are as you describe: Light, longer foot, and the stem allows for a neat Forhan lock wrap. All great features! On the downside, they are a little prone to bending, and that narrow neck is a light braid catching machine, at least in some situations for me. The KT's, having a tiny Y frame design, are less prone to bending in my experience.

I wonder if the extra thread and epoxy needed to cover the L frame foot would make the weight difference less? It would not be much to be sure, but if you are talking milligrams...just curious.

KTs are designed to shed wind knots.

Lynn, are wind knots common? I have had wind knots in fly line leaders but that,s it..not in spin or cast or knots around the rod..Is it more common with spinning..Is it because of closing the bail with the crank and not maintaining line tension to the spool like a beginner does..



Edited 1 time(s). Last edit at 08/14/2022 07:17AM by ben belote.

ben, you use braid. Surely you have had it wrap around the tip of your rod? And not just the tip top, but guides that are further down the blank?

I don't use braid often, and never on spinning gear, but from my experience with braid, its' suppleness allows it to wrap around a guide more easily. And since Fuji even states in its' own literature, that the KR concept was designed with the use of braided line in mind .... wouldn't it make sense to design a running guide that more easily sheds a wrapped line?

As far as what is being said of the L series guides versus K series guides goes. Totally agree. The longer foot makes them easier to wrap. And while the Ls are slightly shorter, or slightly taller (depending on the size guide) than its' corresponding size KT guide, they're easier to handle. Those little line shedding legs on the KT can make them a pain to hold when you're using them in smaller sizes.

I initially started out using all L series guides on my casting rods, but I've built three casting rods with K series guides. I liked that they were said to shed wrapped line easier, and I liked the idea of the wider foot for a mid blank running guide like the KB guide has. I built my most recent casting rod using L series guides, and will continue to use them on my casting rod builds. If Fuji would offer an LB guide. Same length foot, but wider, that would be awesome. I bet they'd sell pretty well too.


And finally concerning the marketing of the K series guide goes. Even though I use fluorocarbon line almost exclusively, the K series guides do shed line wraps more easily.. If I have line wrap around one of my casting rods with KT running guides, it usually only requires that I shake the rod tip a couple of times to clear the wrap. That has not been the case with the rods I have L series running guides on. With those I am usually stopping to untangle the line by hand. So it's not just marketing ..... it works.



Edited 1 time(s). Last edit at 08/14/2022 03:49PM by David Baylor.

A tangle on a guide can be from casting into the wind and getting slack between the guides during the cast with the line catching the guide and looping around it. The more upright the guide, the more likely this is to happen. A guide with a angle toward the tip allows the line to slide back over the guide easier without getting caught. Hence "tangle free", but it will not always be the case. Anytime there is wind the in front of the tip top, the line can also do this near some portion of the tip end of the rod. Very common in fly fishing but also when wading in rough water, casting and retrieving with waves hitting you. Where the line is getting slack because erratic movements of going forward and then backward causing this "slack" with the line wrapping around the tip section. This is when we have to "work" for our fish and it just about wore me out last week.

Ben, what they said. Lol.

Eric very interesting information and I agree with all of your comments at the end.. Ever since the KT guides came out I have been building with them almost exclusively, mainly because of the tangle free design. It works and is very important in my builds. Personally i use braid on spinning and not bait casters and I have really noticed the difference. I have had clients bring me their rods with the L guides on them and ask to totally rewrap using the K's.

Looking at the weight difference if I read it correctly there is only 1.33 grams difference, and depending on the length of the wrap and thickness of the epoxy on a 7' Med Hvy I would be hard pressed to be able to feel the difference although I admit there is some.

On the guide feet if I want a bigger foot use the KB guides, which I use in the power section of all my builds. I did some work on a 7'10" Kistler Rod and was impressed that on that heavy power rod they used the KB guides all the way out. As you noted the K's are definitely are built stronger. When discussing a rod build with a client and we get to the guides and I'll show them both the L and the K and discuss tangle free but also we talk about strength and stress on the guide. They will 99.9% go with the K. The example I give them is, if a single foot is so good why don't they make wheelbarrows with only one handle ?? LOL

On the repair side of my business I get a lot of single foot guides that are broke off at the wrap. Some come in with multiple single foot breaks. Granted that most are abuse but to date not one of my repairs has been to a K frame guide. And we are talking 150+ rods a year for various issues.

What is unique about custom rod building is that we have great options and choices and the bottom line is they both work.

When they first came out with the super lines, I tried some on one of my spin reels then stored away my casting reels forever except for flipping..braid worked so well on spinning for me especially in the wind verses casting, no contest and it,s still no contest..I got into using a bow and arrow cast which can,t be done with a casting reel..Skipping is much, much easier with spinning..just too many plusses..for the B and A cast I used fiberglass rods which I always liked but was surprised how much sensitivity the braided line added to a glass rod so that all I build now are glass rods which are better fish fighting tools than graphite rods in my opinion..and if I keep the glass rods under 66" they feel almost as light as graphite..Just to add that with spinning, line
wrapping around the rod does not seem to be near as much a problem as with casting which has guides on top of the rod usually.



Edited 2 time(s). Last edit at 08/14/2022 09:25PM by ben belote.