Epic REACT Mods and Carbon Fiber experiments

What type of carbon fiber inserts would you prefer?

  • I feel the need for speed... I'm only gonna use them for races, so who cares if they hurt a little

  • I'm all for compromise - give me as much additional speed as you can with all day wearability

  • Give me Cloud 9 - I want the float on clouds feeling all the time, who cares about my time

  • Size 9

  • Size 9.5

  • Size 10

  • Size 10.5

  • Size 11


Results are only viewable after voting.
I wish the entire Infinity was more of the “lofted flyknit” as it just seems to fit better than the Epics ever did over the foot.
I did notice all the flyknit ERs, Phantoms, and Rise's seemed to hug the toes and rubbed as the foot flexed. The new 3 layer mesh (Nike calls it "lofted" flyknit, though there is nothing "knit" about it) doesn't have this issue. I assumed they went to the extreme method of 6 seams in the upper to try and fix the rubbing issue with ERs. I actually like the sock like snugness of the ERs, but it can rub a foot raw. I agree the IR forefoot feels more comfortable, and less "rubby".
 
I don't know if I want to try messing with them. I'll see if I can find something else. I do have pretty flat feet so I've always been using more of the higher end stability shoes over the years. I'm still looking for my ideal combo of stability, highly cushioned, and flexible. The new Skechers GoRun Forza 4 that is coming soon looks intriguing. I may give those a try.
 
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I did notice all the flyknit ERs, Phantoms, and Rise's seemed to hug the toes and rubbed as the foot flexed. The new 3 layer mesh (Nike calls it "lofted" flyknit, though there is nothing "knit" about it) doesn't have this issue. I assumed they went to the extreme method of 6 seams in the upper to try and fix the rubbing issue with ERs. I actually like the sock like snugness of the ERs, but it can rub a foot raw. I agree the IR forefoot feels more comfortable, and less "rubby".

The ER's created an odd sensation for me with that very snug midfoot and looser heel. I just want Nike to pair a traditional upper with the React midsole. Or a knit that is comparable to the New Balance Zante Pursuit. Almost there with the Infinity but I feel they used flyknit to justify a higher price point.
 
Saucony has the closest thing to a Vaporfly competitor coming out very soon. Everyone is hyping the ****e out of it and eagerly awaiting it. And while Saucony spent lots of time with lots of iterations, and had their elite runner eval every new version and rate them, they still didn't get it right. Their elite runner actually tried each iteration on a treadmill with VO2max headgear on, and compared running efficiency. He suggested in a recent video interview that Saucony's running efficiency is better than VF.

Well, I finally found a good video (from WSJ) of the Saucony CF shoe in motion, and nope, they still haven't figured it out. Which surprises me.

Look at these two frame grabs. Yeah, I bet it feels like he's flying, but that doesn't make you more efficient. A good percentage of the energy return is being wasted throwing him into the air. OMG, it looks like he is playing basketball. This is running, not bball. You want all the energy to go forward, NOT UP!

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And let's look at the toe-off. You want flex at the important "Point C". In these two pics you can see the shoe does not flex at Point C. You get the spring effect of the carbon fiber plate bending and launching your toe off, but not the needed flex, and again the toe off vector is pointed up, not forward. The VF and Alphafly nail the toe off to perfection. The Endo Pro does NOT.

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Now let's look at the foot landing and roll forward after heel/mid/forefoot strike. Again, wasted energy return. The mid foot slams down. The endo pro has CF plate toe effect, but does not capture the energy of the foot landing. The VF and AF both capture all the energy of the foot landing and re-direct that energy forward. The EP just wastes it. That is the reason for the "ice cream scoop" shape of the VF CF plate. It captures, stores, and then releases the energy of the foot slamming down. The EP does not.

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Finally, the EP does not have any of what I call "slant" to the shoe. This is an angle built into the shoe sole that lets the foot align with the ground as it first starts to land on the shoe's strike pad. All Nike shoes have slant to them. The Peg Turbos have the most I've ever encountered in a running shoe. It fights the foot and ankle wanting to roll as the foot lands on the outside strike pad of the shoe outsole. Here is a pic of the EPs foot strike:

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Ouch! Look at that ankle roll as the foot takes on the weight of the body.

I really want to like the Saucony Pro, and I really want it to be a good competitor to the VF. However, I don't think Saucony succeeded. Admittedly, I am no expert, and I'm sure I am less qualified that Saucony's shoe designers, but come on, they gotta do better than this.
 
Saucony has the closest thing to a Vaporfly competitor coming out very soon. Everyone is hyping the ****e out of it and eagerly awaiting it. And while Saucony spent lots of time with lots of iterations, and had their elite runner eval every new version and rate them, they still didn't get it right. Their elite runner actually tried each iteration on a treadmill with VO2max headgear on, and compared running efficiency. He suggested in a recent video interview that Saucony's running efficiency is better than VF.

Well, I finally found a good video (from WSJ) of the Saucony CF shoe in motion, and nope, they still haven't figured it out. Which surprises me.

Look at these two frame grabs. Yeah, I bet it feels like he's flying, but that doesn't make you more efficient. A good percentage of the energy return is being wasted throwing him into the air. OMG, it looks like he is playing basketball. This is running, not bball. You want all the energy to go forward, NOT UP!

Screen-Shot-2020-02-28-at-5-54-39-PM.png


Screen-Shot-2020-02-28-at-5-54-48-PM.png


And let's look at the toe-off. You want flex at the important "Point C". In these two pics you can see the shoe does not flex at Point C. You get the spring effect of the carbon fiber plate bending and launching your toe off, but not the needed flex, and again the toe off vector is pointed up, not forward. The VF and Alphafly nail the toe off to perfection. The Endo Pro does NOT.

Screen-Shot-2020-02-28-at-5-55-38-PM.png


Screen-Shot-2020-02-28-at-5-56-34-PM.png


Now let's look at the foot landing and roll forward after heel/mid/forefoot strike. Again, wasted energy return. The mid foot slams down. The endo pro has CF plate toe effect, but does not capture the energy of the foot landing. The VF and AF both capture all the energy of the foot landing and re-direct that energy forward. The EP just wastes it. That is the reason for the "ice cream scoop" shape of the VF CF plate. It captures, stores, and then releases the energy of the foot slamming down. The EP does not.

Screen-Shot-2020-02-28-at-5-56-21-PM.png


Finally, the EP does not have any of what I call "slant" to the shoe. This is an angle built into the shoe sole that lets the foot align with the ground as it first starts to land on the shoe's strike pad. All Nike shoes have slant to them. The Peg Turbos have the most I've ever encountered in a running shoe. It fights the foot and ankle wanting to roll as the foot lands on the outside strike pad of the shoe outsole. Here is a pic of the EPs foot strike:

Screen-Shot-2020-02-28-at-5-56-02-PM.png


Ouch! Look at that ankle roll as the foot takes on the weight of the body.

I really want to like the Saucony Pro, and I really want it to be a good competitor to the VF. However, I don't think Saucony succeeded. Admittedly, I am no expert, and I'm sure I am less qualified that Saucony's shoe designers, but come on, they gotta do better than this.
Jeff Dengate from Runners World tweeted that Molly Huddle had ankle issues with Saucony’s carbon plate racer.
 
Jeff Dengate from Runners World tweeted that Molly Huddle had ankle issues with Saucony’s carbon plate racer.
Call me crazy, but I think the best running shoe right now would be to add a carbon fiber plate to Saucony's Freedom 3 shoe. The shoe has a lightweight beaded TPU foam that is lighter than boost and has great energy return. The upper, heck the whole shoe is super flexible. The only problem is it is too flexible and nothing channels that energy return into forward motion. The super flexibility will definitely strain all the muscles of the foot and cause cramping and issues if used for the 26 miles of a full marathon. Adding a CF plate like I made for the Epic REACTs would make it killer. And I'm not the only one who thinks so. RoadTrailRun's owner commented that Saucony should have put the carbon fiber rock plate from their trail shoe into the Freedom 3. I agree 100%.

I am getting 5.5% economy of motion improvement from Epic REACTs with crappy synthetic rubber foam after 300 miles of running data. I bet I could get 8% out of the Freedom 3. However, I don't really want to spend the $5K on a new mold for the Freedom 3, and I'm currently all out of my CF supplies. I don't race anyway, so I'm only competing with myself and my own PRs. PEBAX foam (Nike's ZoomX) is a mixed bag. It has the maximum energy return you can get, but it is only a few % better than the latest TPU foams, and it has lots of issues like instability. In other words, it is hard to control the energy return of PEBAX and tame it.
 
Here is a screen grab of when Gwen reviewed the Pegasus Turbo. Notice the "cant" to the shoe. There is an angle to the bottom of the shoe that makes the outside strike pad higher than the medial side of the shoe. This would seem to be the opposite of what you want, the worse thing you can do. However, it is actually the best thing you can do. As the foot lands and pushes off, it fights the ankle rolling and lets a runner really push off with max power. The Turbo has the most cant of any shoe I've ever seen, which I assume is because the midsole combination of REACT and ZoomX is so soft, they had to increase it over the normal Pegasus.

The Saucony Endo Pro has zero angle, and the bottom of the shoe is nice and perpendicular to the centerline of the upper. Which would intuitively seem best, but in reality it will let the ankle roll during landing to toe off. Especially when coupled with unstable PEBAX foam.

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This pic from RoadTrailRun's review of the Freedom 3 shows the issue with not enough structure to the shoe.

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However, I encourage you to look at Jami's review of the show, especially this section on slowest playback speed. The shoe has the best landing, transition, and toe-off of any shoe I've looked at. And it is not just Mary-Beth's perfect running form. The shoe is amazing. It just needs some help with a plate. Unfortunately, I currently do not have the time nor money to make a plate for it. Maybe later this summer.

 
Running Warehouse just posted a video with the Director of Engineering at Saucony, Andrea. She discusses the development of their Endo Pro with carbon fiber plate.

Here is where she talks about and shows the carbon fiber plate.



Here are a few screen grabs that show the shape of their plate.

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Andrea says they started with that plate design and never tried another shape. They focused on the midsole durability and upper type. She should have focused on the plate shape. I started with that shape over a year ago and quickly learned its shortcomings and moved on to better designs. She also mentions their runners saying they feel like a different set of muscles are being used with this shoe, which I also found, which is what you don't want. Long story short, the stiff gently curved forefoot is altering the runner's natural stride. This will result in injuries.

Nike is so far ahead of the competition it is amazing. Saucony's "beaded" pebax is an improvement, but they got the plate shape wrong, the midsole shape and angles wrong, offset wrong, and foot landing, transition, and toe off wrong in the EndoPro. I'm going to stick with the Freedom 3 for now (and of course my Nike shoes).
 
I've been watching the Atlanta olympic trials today, all the various videos, zoomed in on the feet. The Alphafly's seem to have absolutely perfect form, heel strike, transition, and toe-off. I wasn't sure how the very high stack height and zoom pods in forefoot would work. But, the shoe looks amazing during transition. I don't think the zoom pods are a gimmick, as you can see them compress and then release at just the right time. When the runners are on their forefoot the shoes seems to still be stable. When they are going downhill which forces a midfoot strike, the shoes still seems to be stable in the transition to the separate forefoot structure. I saw some tired runners accidentally heel striking, and again the shoe seems to correct itself and force a good transition to toe-off. Quite amazing for such a dramatically different shoe. Nike really did their homework on the AF.
 
How did you come to notice many of these motions?
Nothing fancy... Just spent the morning watching coverage of trials. Then I screen grab the various videos, zooming in on the shoes, and then slowing everything down as much as possible, sometimes single frame advancing. The video coverage and quality has gotten much better of running events, with better resolution, and more focusing on the shoes.

For example, here is the AF after forefoot landing, at max compression of the zoom pods. Though short slo-mo video clips are more enlightening than just still frames:

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I thought maybe the zoom pods in the AF would create instability at forefoot landing, or perhaps the wedge shaped rear portion of the midsole would act like high heels during heel landings and cause ankle rolls, but I saw neither.

I guess Nike had some sort of event for runners before the trials and gave out lots of AFs, so plenty of runners had them on. (Though lots of runners were still in their VF Next Ekidens.) Here is a video from Evan Schwartz talking about the AF giveaway:



And the runners all had very different running strides. Some were on their toes the whole time, others struck midfoot and rolled to toes, and as already mentioned, some tired runners slammed their heel down and rolled on through the transition sloppily. I was impressed to see the AFs work well with any running style. I thought they were for forefoot toe runners only.
 
Since all the shoe hype of the last couple years, the cameras do seem to zoom in on the shoes more than they used to... and with the latest high resolution, high frame rate cameras, the still frames are much sharper than in the past.

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Info on Brooks CF plate, from RunnersWorld video review.

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As you can see, similar to VF plate design. A bit less ice cream scoop curve. A bit less midsole foam above and below it. The CF plate has an extra stiffening layer down the center. It stops just past the important Point C, allowing proper toe off (I assume the last cm or so flexes).
 
This vid has some good slomo of the AF on a track. A bit blurry, but you can really see the foam, plate, and pods in action:

 
When watching Gwen's latest video, I noticed another runner's shoes had the best toe off of any shoe I've seen. After watching footage of this runner over and over, the landing, transition, and toe-off spring is incredible. The energy return vector is almost straight forward, and you can see her get launched forward with each step. Yes, her perfect form and strong legs are a big part of the story, but the shoes look amazing. After zooming in on the shoe CW, I determined the runner had New Balance FuelCell XX on. I say XX as the upper looks like the TC and but the outsole doesn't match the TC or RC, not sure exactly what model it is.

Watch the following video from 1:08 to 1:28 at 0.25 speed and look at the NB shoes and compare them to Gwen's VF:

 
Yeah, it's been a while since posting. I've been happy with my shoes and plates so I've just been running. I've put over a thousand miles on my shoe rotation. Surprisingly, nothing has worn out yet.

It seems everybody makes a carbon fiber plated shoe these days. I keep getting asked which is best and why, and unfortunately I can't answer that. First, everyone is a different size and weight, and the plates only come in one spring rate, so you gotta see what works best for you. Second, I'm not really happy with anything out there.

My main problem with ALL the CF plated shoes is heel instability. They all have tall stack heights of unstable foam at the rear of the shoe. Which is ironic, as the heel foam has little to no contribution to energy efficiency or energy return.

Nike has actually solved this ZoomX heel instability problem - but in their training shoe, the SuperRep Surge. They gradually taper the ZoomX foam more narrow towards the heel and have a firmer foam (in this case Lunarlon) gradually taper wider. Here are some cutaway pics from 포모스트 on YouTube:

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I don't think the Surge would make a very good running shoe, so I hope Nike bring this technique to their running shoes. Nike tried to stabilize the Invincible Run shoe by making the ZoomX massively wide on the bottom. That doesn't really add the right kind of stability. The Turbo approach was much better, using REACT to stabilize the ZoomX.

What am I trying next? I'm excited about rumored lower stack height plated shoes with ZoomX from Nike. I also want to try the Saucony Freedom 4 when it comes out, as the Freedom 3 is an amazing shoe (I added a plate to the 3 and hope it fits the 4).
 
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Here's a pic from Corriamone on YT. It shows the internal structure of Adidas Pro CF rods. For those who have asked for my opinion, I have none, as I have not been able to find them in stock yet. I did notice that the marketing X-ray photo that shoes the rods in alignment with the metatarsal bones is faked, as the rods in the midsole are shaped differently than in the x-ray.

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Wow, look at the built-in cant to the Adidas SL20! (pic from Runnersworld review)

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That's one of the first things I look at in running shoes - and anything with built up support on the inside gets rejected immediately - because it kills my knees. I'd actually rather have about the same tilt in the opposite direction - but my biomechanics are pretty screwy so there's probably not much market for that.
 
Here is a pic from EDDBUD of his Adidas Adizero Adios Pro. Note how you can clearly see dirt marks where the carbon fiber rods are. I think this may be a good thing, as it shows the rods are really taking a heavy load rather than just floating in the foam, but TBH I'm not sure what to make of it...

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Good pic of what's inside the VF, in this case the VF2. I like the new upper seamless design. And not all CF plates are equal. I've taken apart most CF shoes, and somehow Nike's are tougher, stiffer, and have a complex curve to them. Amazing.

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Just ordered a pair of UA flow velociti winds, for several reasons.
1. I'm curious about the new midsole foam made by Dow. It is also used by Salomon.
2. The mapped outsole shape and pattern is similar to the Epic React.
3. Reviewers said it had the firmness and stability of React with the bounce of new superfoams, a good compromise in the middle of the two.
4. The foam is supposed to be temperature insensitive, and I'm tired of React getting brick hard in the cold.
5. It appears in pictures to have a good flex at the critical point C.
6. In slow motion videos, it seemed to have a perfect transition from heel strike to toe-off.
7. I'm curious about the new upper technique of overlapping tapes and threads.

If I can scrounge up enough materials, I might try to make a plate for it, as I don't think anyone has tried this foam with a plate yet.

Reviewers have said it does not have the pop or energy return of a VF, so I'm not expecting a miracle, just hopefully a nice running shoe.

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Just ordered a pair of UA flow velociti winds, for several reasons.

I'm sending my UA Velociti back after only one run. I was hoping this pair would give the natural motion of a minimalist shoe with the protection of a foam shoe. Instead, it gave the worse of both worlds. They were as punishing as running in barefoot shoes, yet the upper constrained the motion of my supporting muscle groups and prevented them from proper motion. Some pros and cons:

Pros:
1. These shoes have the best heel to toe motion of any I have ever worn. No matter the foot strike, my foot had perfect motion. It was like a coach was holding each foot and making it "flow" perfectly through the foot strike.

2. The threads and tapes of the upper worked great. When accelerating, decelerating, cutting back and forth, my foot transferred all the energy to the ground. I can see why these make good basketball shoes. The threads and tapes overlay worked better than Nike's flywire.

Cons:
1. Very punishing midsole. Yeah, it is supposedly foam, but mine had zero give. It was like running in a solid plastic shoe. Maybe I got a bad batch of foam that had the wrong mix of additives or cured at the wrong temp. Not sure.

2. The upper had too little volume. The length was TTS, but my low volume feet barely squeezed into the upper with thin socks and laces loosened.

3. Shoes had no pop or speed. They matched my average shoe time for the route, which makes them 4% slower than my VFs.

So, to summarize: They are too firm to be daily trainers, yet too slow to be race day shoes, so what is their purpose?
 
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