Thursday, October 18, 2018

Vaporfly 4% Flyknit Initial Impressions and Race Review. Near Perfect for 1:07 & 1:40 Half Racer/Testers. Comparisons to the Original Vaporfly 4% and Zoom Fly Flyknit

Article by Sam Winebaum and Cheyne Inman
Nike Zoom Vaporfly 4% Flyknit ($250)
Sam: Racers from world marathon record holder Eliud Kipochege to my fellow reviewer Cheyne Inman with a recent 1:07:08  half in his pair to slow old me a 1:40:26 in mine have been literally captivated by the Nike Vaporfly 4%, by the chase to try to find this rare shoe and the results which have been for the vast majority faster than expected at all distances and with less leg fatigue.

Most and we do to agree that the combination of very light weight for cushion, copious amounts of responsive soft Zoom X foam and an integrated full carbon plate for stability and propulsion with the resulting trademark "fresher legs to the finish" are the key factors in the racing and even training success of this shoe for so many.
I have been delighted by every one of my performances in them- multiple halves and 10K, a 5K, and a marathon),  My pair for all but 2 races (Obsidian) has been from the very original July 2017 baby blue color release with now 130 miles of hard racing (review here) and no wear in sight. Subsequent releases had minor tweaks.
For example, I found the Obisdian somewhat firmer than the original and its mid foot upper down low had less volume and was more secure, a good thing as my original require a thicker Stance Fusion merino sock to take up volume.

Launching this September the Vaporfly 4% Flyknit gets an all new stretch knit upper substituting for the engineered mesh of the original.

This upper is very similar to the new Zoom Fly Flyknit's shown below, and which we will also discuss here, but essentially the Zoom Fly substitutes heavier and less expensive React foam for the Vaporfly's Zoom X foam and also has smaller full carbon plate.. along with a lower price of $160.
The changes to the Vaporfly 4% are clearly focused on better locking down the foot toe to heel, less volume but now stretch volume The result is essentially putting a race shoe upper on the Vaporfly's largely unchanged undercarriage.
I say largely unchanged as the new Vaporfly when run side by side one on each foot with my 130 mile pair is also very slightly firmer from what I can tell and notably more stable at the heel, an issue with the original for me and many on uneven pavement and steep downhills as the original could some be down right scary in those conditions. This new found stability and heel hold is due to the inclusion of a considerably more substantial heel counter in the new Vaporfly

What is going on with these changes? Well I suspect that just below the top few Nike elites who got the custom tuned Elite version that while loving the original "standard" consumer version ride other elites wanted a more dialed in race upper. We saw such prototypes over the last year. Further, so there would be no question in terms of IAAF and other regulations, I believe Nike thought it was important that the public could buy essentially the same shoe as potential record holders and that previous supply issues needed to be "reasonably" taken care of.  And it appears this release had significantly more pairs available. As far as the ride of the new Vaporfly, my initial sense, and in keeping with the elite focus, is that it is somewhat firmer than the original with a touch less bounce but a more "taut" feeling springier effect which could be related to a now more snug upper with its increased support that better keeps the foot on the platform to fully take advantage of the famous carbon plate or other unseen and unannounced changes to the plate itself.

Weight all US M 8.5
Vaporfly 4% Flyknit: 6.42 oz /182 g
Vaporfly 4% Original Blue: 6.56 oz /186 g US
Zoom Fly Flyknit: 8.325 oz/236g
10 mm drop

Fit and Upper
Sam: The new Flyknit Vaporfly fits me true to size but with caveats. The front stretch knit over the big toe area is quite dense and low on try on even as length is correct. After my initial 6 or so miles it has clearly stretched some in that area. Otherwise the fit is as one expect in a top level racing shoe, secure and snug and not at all like the fit of the original. Here I need to wear thin socks while in the original I wore thick Stance Fusion merino to get an adequate fit. I have heard many have sized up a half size in the Flyknit. I would too for sure if I wore thick socks but so far with a half race to come the fit is...fitting of a race shoe.  Update: for my recent half I wore thin Compressport race socks and the fit was perfect, plenty of toe box volume now that the mesh has stretched a bit. Would without question wear this combination for a marathon.  This said I may still use the original for marathons on flat courses as I did when I got my Boston Qualifier this spring, but for under marathon distances or hills the stability of the new upper and real heel counter is where I will lean.

Cheyne: I would agree with Sam on the upper fit, I went with my normal size and did not size up and the fit was perfect. I did also notice that the area over my big toe felt a little shallow, but it has stretched some after about 40 miles and I do not notice any rubbing from it. I have raced in them for a 10k and a half marathon and have not gotten any blisters.
The original had a most unique fit for a race shoe. Its non stretch engineered mesh provided a commodious very high volume toe box, a roomy mid foot and no heel counter. Note the amount of medial upper collapse on my well worn original Vaporfly. Less noticed on the run than visible but surely a factor in comparison to the taut directed upper and feel on the new version.
Some with narrow feet sized down with the original Vaporfly. There was no give to the upper to go with the room. I was true to size in the original and adapted with thicker socks. Zero blisters or any issues during my flat marathon  in them or any other race. On steeper downhills and uneven pavement the fit was let's just say at times shaky.. The later Obsidian version clearly snugged things up at the mid foot and was an improved upper.
The Flyknit upper, in sharp contrast to the original's is a stretch knit with no overlays or reinforcements and also thankfully no FlyWire either which the original Zoom Fly had and potentially the original Vaporfly could have used.
All the support comes from the varying densities of the knitting of the upper and it is one heck of an upper.
It has a snug and comfortable fit but its denser mesh over the toes is felt whereas in the original there nothing felt over the toes, no pressure was felt just well held if spacious height and width.
This is clearly a more race performance fit upper and for me more suitable for sub marathon distances with the jury out on marathon use for me and their potential foot swelling but this it is important the upper does have some stretch.
The Zoom Fly Flyknit has a nearly identical upper with somewhat more height over the toes.  
LEFT: Vaporfly 4% Flyknit                                      RIGHT: Zoom Fly Flyknit
The Zoom Fly knit itself appears to be almost if not identical to the Vaporfly's in its density and stretch at the toe box with the Vaporfly seeming slightly less stretchy and slightly thinner at midfoot.
LEFT: Zoom Fly Flyknit                           RIGHT: Vaporfly 4% Flyknit

Zoom Fly Flyknit      
The Zoom Fly has a nearly if not identical ankle and achilles padding but a slightly wider foot opening and greater mid foot volume.

BOTTOM: Vaporfly 4% Flyknit             TOP: Zoom Fly Flyknit
The use of Flyknit distinctly improves the mid foot hold vs. the original where there was a fairly distinct sense of medial collapse, actually I kind of liked the feeling there but it was overly roomy.
Another key improvement is a beefing up of the heel counter and "narrowing" of the ankle collar through stretch knit vs the original's non stretch and overlays to better stabilize the heel area .
The original (right) had essentially no heel counter beyond a touch of vertical stiffening, the red strip.
The Flyknit while not having a firm traditional heel counter now has plenty of heel support from the some stiffening down low wrapping the heel and the denser thicker padding around the sides of the achilles collar.  Up higher at the achilles in front of the pull on strap there is no padding. I definitely will not be wearing no show socks here.
The result is a far more stable heel than the original with so far fewer issues on steep downhills or off camber pavement.
Bottom line for me is that I prefer the now secure heel and mid foot hold of the Vaporfly Flyknit but miss the spacious toe box of the original. A good compromise given we have a single piece all knit upper here was to adopt a bit more of the height of the Zoom Fly in the front of the toe box to the Vaporfly

The special magic of the Vaporfly 4% is the midsole combining very light energetic Zoom X PEBA foam and a full length carbon plate. The carbon plate sits about a half inch down below the foot at the heel (at the crease above the lettering below), plunges at mid foot, and then is located just above the outsole up front. The plate location at the heel above the Zoom X insures a well cushioned but short time lingering at the heel. The front plate location insures cushion up front for the toes but then an explosive take off when downward forces meet the plate. Essentially the plate up front acts much in the same way as a spike plate in a track shoe, a stable firm platform for push off.

Cheyne: Although I did not experience a magical burst of energy from wearing these shoes, I believe they drastically cut down on fatigue and post race soreness. My calves particularly do not feel the typical wear and tear that I experience after racing in a low profile racing flat, and this protection is what I believe aids in race performance over longer distances. I was even able to cool down in the shoes after my race and they felt soft and comfortable jogging at slower speeds.

There are no visible changes to the outsole or underside geometry.  Most will scuff the white painted Zoom X but this wear is entirely cosmetic. My original (left) with over 130 miles of mostly hard racing have quite frankly minimal wear.

Cheyne: The outsole does not stand out as an outsole that would offer much grip, but I have worn them on some slick concrete paths and had no issues.
The Zoom Fly has very similar outsole and exposed midsole geometry but with some differences. The front pentagonal pads are slightly concave while the Vaporfly's are flat.
They both share slightly concave rubber heel pads. The Zoom Fly has deeper center midsole cavities.  I find the Zoom Fly slightly softer overall particularly at the heel from from these deeper cavities and I assume the React foam and the narrower carbon plate

The Vaporfly 4% Flyknit's ride is not significantly changed as all materials and geometries, including the outsole "appear"unchanged. This said the Flyknit's midsole and ride feels somewhat more "taut"  as if the carbon plate is springier with a touch less of the soft bounce of the original. Overall one can say the new Vaporfly is more responsive, more in keeping with an elite performance profile than the original which was ever so slightly more friendly and cushy. The later Obsidian recent release had a similar midsole feel but I felt also has less spring than the Flyknit. While I have no confirmation of changes to the carbon plate some report a snapping sound when running or maybe more suction from the outsole. I definitely was hearing something different when compared to the original.  The Flyknit for sure feels more directed in the line of travel with a more distinct and firmer spring. Could this more directed and springier feel be in part due the effect of a more secure upper and heel counter that causes this sensation by better mating the foot to the platform? Hard to say but definitely possible.

Cheyne: Very smooth ride because of the amount of cushioning this shoe offers. I think it will work well for midfoot, forefoot, or heel strikers.

Race Results and Update
Cheyne just won the Ventura Half Marathon in his Vaporfly Flyknit in a near PR time (within 11 seconds) ) of 1:07:08!
Sam: I ran the Baystate Half at Lowell, MA in the Vaporfly Flyknit losing first in my Age Group in the final mile and confirmed my initial impressions that the Flyknit is slightly firmer and less bouncy than the original. It is more responsive but a little harder to keep in the forward lean groove and bounce away ride of the original. It is clearly more stable on rough pavement and downhills at the heel and midfoot but still a bit tippy on off camber pavement.
Conclusions and Recommendations
The new Vaporfly 4% Flyknit gains a performance fit stretch knit upper which eliminates the heel and mid foot play of the original's non stretch engineered mesh but which has less toe box volume and height as a result. It is important to note the upper does stretch and initial try on may not be what they feel like with a few miles on them as I found out.  

Some may find the need to size up but so far I am OK at the same size as my original Vaporfly using thin instead of thick socks. While "comfort" may have suffered a bit, making the original a potentially more comfortable marathon shoe for mere mortals such as me, the Vaporfly is now more directed given the foot is really locked to the upper. Heel stability is notably improved given the inclusion of a heel counter so steep downhills and uneven off camber pavement is no longer as "scary". Midfoot medial collapse is reduced via the snugger lower volume knit construction.

I am also sensing, and the new upper can be a factor as the foot is better locked down, that the ride is springier, more taut and dynamic and not quite as soft and bouncy. There is no question, and results from a world record to countless smiling PR, that the Vaporfly 4%'s combination of very light weight for the cushion provided and dynamic propulsion from the carbon plate continues to provide a very special running experience of speed and very fresh consistent legs to the finish and in recovery days after. The best race shoe I have ever run bar none.
Sam’s Score: 9.85/10
I would score version 1 and version 2 about the same but for different reasons. With version 2 here the loose upper issues for which I would deduct are well fixed but with version 2 we get a slightly firmer less bouncy ride which is harder to maintain in the special Vaporfly groove. For both I would also deduct a bit for the very high price of admissions.

These shoes are currently my most prized possession. I have raced in them twice and they definitely live up to the hype. I do not feel that they make you faster from a midsole rebound standpoint, but I do think they help with lower leg fatigue which translates to better form and energy return at the end of a marathon. I believe that this energy will lose some of its pop the more you use them, so I will be limiting their use. If the Vaporfly 4% were less expensive and more easily available I would absolutely use them for workouts and races, but because of this I will be saving them to wear at my goal race in December at the California International Marathon. I did not size up in this shoe and they fit me perfectly for a racing shoe, very snug in all the areas I need support.
Cheyne’s Score: 9.9/10 
I absolutely love this shoe and I would give it a perfect score, but I would like it to be about an ounce lighter for a more race-like upper feel.

Watch Cheyne Inman's YouTube review of the Vaporfly 4% Flyknit!

Nike Zoom Fly Flyknit (RTR review)
Sam: Topped with for all intents and purposes with an identical upper with slightly more volume, the Zoom Fly substitutes React foam for Zoom X and uses a narrower carbon plate. It is nearly 2 oz heavier and weighs $90 less. The ride is slightly softer at the heel but not quite as dynamic and a bit bottom heavy as the 2 ounce difference in weight is felt and React is just not the silky smooth Zoom X in feel. This said, at just a shade over 8.5 oz in a US men's 9, it is clearly a trainer compliment to the Vaporfly and a fantastic if a bit tuned down up tempo trainer and racer. I call it a Zoom Fly "2.5%" as I did in my review linked above.
Cheyne: The Zoom Fly is the only shoe on the market that compares to the feel and energy conservation that the Vaporfly offers. I like to use the Zoom Fly for workouts(it costs less), but I like the bouncier feel and lighter weight for racing that the Vaporfly offers.

Skechers Razor 3 Hyper (RTR review)
Cheyne: The comparison I see in these two shoes is that they both have enough midsole to leave your legs feeling more recovered after a hard effort, but they are light enough to run fast in. The difference I see in the shoes is obviously the price, but also that the Vaporfly 4% is firmer and more responsive, but the Razor 3 is lighter. If the Razor 3 had the the Carbon Fiber plate that the VP4% has, I would go with the Razor 3 as my race day shoe.

Reviewer Bios
Cheyne Inman competed in college at the University of San Francisco where he was the first athlete in school history to win the West Coast Conference Championships. After college he was a head coach in cross-country and track at the high school and collegiate level before moving on to managing athlete sponsorships at Skechers Performance. Currently he is coaching the 2017 California State Championship team at West Torrance High School and pursuing a career in real estate. He enjoys running in neutral running shoes for the trails, track, and road and typically runs over 100 miles a week. He has pr’s of: 5k- 14:36 10k- 30:23 half marathon- 1:06:57 marathon- 2:25:38
Sam Winebaum is the Editor and Founder of RoadTrailRun. He has been running and shoe geeking for 45 years. As he turned 60 in 2017 he was thrilled to clock a 1:35.24 half and as he turned 61 a 3:40 marathon to qualify one more time for Boston. Sam runs his roads and trails in coastal New Hampshire and Park City, Utah.
The product reviewed in this article was a personal purchase. The opinions herein are entirely the authors'.
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The first release of the Vaporfly 4% Flyknit is currently largely sold out but more are sure to emerge. The Zoom Fly Flyknit has more availability

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demian said...

Not feeling worthy of the Vaporfly, I think I've found a good rotation in the Gorun Ride 7 and the new Zoom Fly FK. Either could work for my first marathon Nov 4th.

Rachel said...

Love, love, LOVE this shoe. I never tried the original vaporfly, but the Flyknit version is just about the comfiest marathon shoe I’ve ever worn. I just wore them for my first postpartum marathon and knocked off a whopping 5 minutes from my PR to nail a 2:49:43 on a very similar course to my previous PR.

I got a men’s 6.5, which is like a women’s 8 and the sizing was spot-on. It’s definitely a race fit, and I was worried the toe box would be too snug but the upper is just stretchy and forgiving enough that I got no hotspots at all, did not even have sore toenails the day after my marathon. The shoe needs pretty much no breaking in. I did two short runs of 30min and 20min the few days prior to my race, more to dial in my sock choice and the lacing.

It’s not so much that I felt significantly faster in the VF, but that it was less battering to my joints to maintain a strong pace. I also did not get that slapping, dead feeling in the forefoot over the last 10-12k, which has often been an issue for me and caused massive blisters under foot in other shoes. Consequently, I was able to maintain a better turnover, felt punchier and finished faster.

Given the price point of the VF, I daren’t use it in training. I’m curious what you guys recommend using as a trainer to simulate the VF but with a touch more protection and durability? It’s so different from the Zoom Fly (which feel much harder and bother the balls of my feet after 8-10mi) or my usual Hoka Clifton/Altra Duo.

Sam Winebaum said...

Hi Rachel, Congratulations on your stellar marathon! I totally agree that the key to VF is fresher legs. I find I maintain a much more consistent pace at all distances and even occasionally have a kick, Closest to VF the new ZF Flyknit no question. I too found the original punishing and with a narrow pace range for me. The new ZF is a softer ride but not quite VF soft. It is more stable than VF and a super fine option. You might also look at the Reebok Floatride Run Fast ( has a form of the same PEBA foam as VF but a touch firmer) or Reebok Sweet Rpad 2 a more conventional light trainer with a nice soft forefoot and stable heel and only $100 with a super and simple upper.
Sam, Editor
Thanks for reading Road Trail Run! See our page with links 100’s of in depth shoe and gear reviews HERE. You can also follow RoadTrailRun on Facebook, Twitter, YouTube and Instagram where we publish interesting run related content more frequently as well as links to our latest reviews. Shopping through links on articles help support RoadTrail Run and is much appreciated!

Mark said...

Hi Sam,

I have a simple question. I'm trying to find a race day shoe for my upcoming first half. Being new to racing (and slow compared to most here) I don't believe the VF is suitable for me. My target for the half is about 2:00:00. What shoe would you recommend? Would the ZF FK be a better choice?

Sam Winebaum said...

Hi Mark, Thanks for asking. What do you train in now? That shoe might be most appropriate as a first race shoe unless it is super heavy. ZF FK might be a good alternative as would Brooks Launch 6, adidas Boston 7, Saucony Kinvara 10. Reviews of all at the link below.
Sam, Editor
Thanks for reading Road Trail Run! See our page with links 100’s of in depth shoe and gear reviews HERE. You can also follow RoadTrailRun on Facebook, Twitter, YouTube and Instagram where we publish interesting run related content more frequently as well as links to our latest reviews. Shopping through links on articles help support RoadTrail Run and is much appreciated!

Mark said...

Sam, I train mostly in the Asics GT-2000 6, which I find to be a decent stability-oriented daily trainer, but I believe it's too heavy and firm to be a race shoe.

I am therefore considering the ZF FK as an uptempo/race day shoe, but will also try to check out the other options you mentioned. Thanks!

Sam Winebaum said...

Hi Mark,
If you need a bit of stability in a race shoe Kinvara 10 is a great choice as might be the adidas Tempo 9. Firmer and maybe not quite right the Brooks Asteria,
Sam, Editor.

Sam Chua said...

Hi, would you use the Reebok floatride fast or the Vaporfly for a 3km road race?

Anonymous said...

Hi, when you say they fit true to size, do you mean that you would order in the same size as a normal shoe or your usual running shoe?
I’m a size 10 in normal footwear a size 11 in Adidas Boston’s and 10.5 in ASICS DS Trainers - when I foirst started running I was to,d that you needed a larger size as the foot swells during running

Thanks in advance for your help


Sam Winebaum said...

Hi Anonymous,
Sorry, always running shoe size for comparisons. I might go with 10.5 understanding that the stretch Flyknit felt low over the toes in my true to size initially and improved with wear but will still be a race type fit there and all ove,r unlike the original Vaporfly which was very roomy, some even sizing down from normal. I didn't but wear slightly thicker socks with those. Going to big in VF Flyknit could make it sloppy, unstable
Sam, Editor

Anonymous said...

Thanks Sam

Unfortunately I can’t get a 10.5 in the UK at the moment, so will probably order a 10 and 11 and see how they fit

Thanks again


Unknown said...

Wondering how these would do in packed trail such as Tunnell Marathon in Seattle?

Phil M said...

Even if this shoe didn't make you faster, i'd still run in it! It's the only shoe that actually enhances the whole experience of running.

Ash Green said...

It was really insightful.
Thanks for such a nice content.
BTW if anyone interested more have a look theshoesfinder thanks

Radulle said...

What is your experience on the longevity of this shoe? How many miles should one expect to get from them? Does it make sense to use them for a 5k race?

Sam Winebaum said...

Hi Radulle,
My original VF pre Flyknit has over 170 miles of racing on them with little wear and only a touch less bounce. Many are reporting many hundreds of miles rotating the race shoe to training after about 150 miles or so,. The Flyknit version is firmer than the original so I would retire a bit earlier from racing. Absolutely for a 5K. The NCAA 10K race was won in a pair, But would caution if course has lots of turns or uneven pavement a more conventional race flat would be better.
Sam, Editor