Article by Bryan Lim and Ryan Eiler
Nike Streakfly 2 ($190 USD / AUD $250)
Introduction
Bryan: With all eyes on the release of the Vaporfly 4 (VF4), it is not surprising that its little sibling the Streakfly 2 (SF2) has gone a little unnoticed. But this should not be the case as it has been completely redesigned from its predecessor which was released a full three years ago. A lot can and has happened in that time for both the Streakfly lineage and also the plated shoe scene. The SF2 now sees a decreased stack height from 32mm to 27mm and a decrease in drop from 6mm to 4mm, and the introduction of a full length carbon fibre FlyPlate. Essentially what we have is a trimmed down VF4.
The plated shoe scene is now ever more saturated; some say the VF4 is no longer a marathon shoe and would be great for a 5k up to a half, whereas the intended purpose for the Streakfly would be for a 5k. On the other side of the fence, Adidas has adopted a different philosophy with the less aggressive Takumi Sen 10 (and soon to be 11) for shorter distances and the Adios Pro 4 which is capable of most distances up to the marathon and possibly beyond, occupying the space that the VF4 and Alphafly 3 take up (discounting the illegal Prime X of course). Without having worn the original Streakfly, my contention is that the SF2, and contrary to ‘‘road racing’ printed on the midsole, is a great track shoe and is only more suited for elite road runners to race in.
Ryan: My colleague Bryan has delivered a superb initial review, and I find myself echoing many of his sentiments on this new Streakfly. Where I can perhaps add some value is by comparing the shoe to its predecessor, the Streakfly 1, which I was fortunate enough to test upon its initial release (RTR Review).
What strikes me as most pleasantly surprising is the significant increase in stiffness in this second iteration. While the first version was gloriously light and nimble, it fell short in performance for me. Its midfoot 'shank' offered almost no perceptible stiffness or stability, resulting in a "wet noodle" feel when trying to put down serious power—precisely what the shoe is designed for. It's heartening to see that the design team has addressed this by incorporating a hearty, full-length carbon fiber Flyplate that performs admirably. While it doesn't reach the stiffness of a Vaporfly, it's a massive step in the right direction and befits a shoe built for hard, short-distance efforts.
Pros:
Ground/track field, if desired- Bryan/Ryan
The updated engineered mesh upper offers incredible lockdown - Bryan/Ryan
Feels extremely light on the foot - Bryan/Ryan
More forgiving than most spikes
Phenomenally grippy outsole
Cons:
A very specific shoe that is often not required in a rotation, i.e. lacking in versatility - Bryan/Ryan
Harsher than most other road shoes - Bryan/Ryan
Limited to forefoot strikers - Bryan/Ryan
Durability (likely) - Bryan/Ryan
Stats
Sample Weights: Mens US9 4.44 oz / 126 g, US9.5 4.50 oz / 128g
Stack Height: Heel – 27mm, Forefoot – 23mm (4mm drop) (reduced from 32/26, 6mm drop )
I would like to note that my measurement of the forefoot and heel both come in at 30mm.
Platform Width: 70 mm heel / 62 mm (tapering to 41mm which is the width that contacts the ground) midfoot / 99 mm forefoot
First Impressions, Fit and Upper
Bryan: My first impression of the SF2 was fear, and fear that I would not be able to do good enough to bring out the best in the shoe! Fears aside, it is apparent how aggressive they are when putting them on. You feel some of the softness in the ZoomX foam, but the structure created by the plate and aggressiveness of it is immediately apparent. You will also note that the SF2 appears to have a close to a zero drop (see foot away from the camera in the image above, and the below image) and I believe the claimed 4mm drop is for when the shoe is in its intended ‘racing state’, i.e. titled forwards on the forefoot. Further and as noted, my measurement of the fore and rearfoot come in at 30mm, which could also be a reason for the visual appearance that the SF2 does not have a drop.
The fit is absolutely perfect and true to size for me. I would note that the toe box width may be restrictive for some, but the overall length and width in my size provided the perfect fit. In the image, my index finger points to where my big toe bulges slightly over the width of the platform, and does so even without socks on. The upper is forgiving enough such that even with this, there were no hot spots or areas where I felt undue pressure on. What can be said is that the toe box volume is surprisingly generous. This was not an issue for me as I can easily fit into narrow shoes (e.g. the very old Adizero Adios 3). It is imperative you try these in store before purchasing.
The tongue is strategically padded thin, non-gusseted with a non-symmetrical v-shaped finishing (see below image) to wrap around the base of your ankle. The heel collar is also minimally but strategically padded. The mesh upper is also minimally but strategically reinforced in the heel cup and forefoot. You see what I’m trying to say? Everything is minimal, and all concessions made to provide comfort are done so intentionally and are done so for a functional purpose.
Minimal but necessary heel collar cushioning with a nicely designed anatomical asymmetrical V-shaped tongue
Minimal but necessary toe box reinforcement
Ryan: While it's not a track spike, the Streakfly 2 leans more in that direction than towards a typical 'super shoe'. It's lean, hyper-light, and boasts a tenacious, racy fit that demands forefoot propulsion. It feels very aggressive underfoot and, as Bryan noted, has a minimal heel-to-toe drop.
It wouldn't be a stretch to consider this a comfortable track shoe without the spikes, given its low weight and eagerness to turn over quickly. For comparison, the Nike Dragonfly track spike has a stack of approximately 20mm/18mm, while the Streakfly 2 sits at 27mm/23mm, placing it closer to the track than the 40mm 'super' territory. It does still sit above the World Athletics 25mm heel height limit for track races over 800 meters.
The fit is true to size; however, it’s important to remember that this is a racing shoe. It’s narrower and hugs the foot more tightly than a standard trainer of the same size. Like Bryan, I'd recommend trying this one on first if possible to ensure a proper fit.
Midsole & Platform
Bryan: As discussed in the prior section, I would describe the overall platform to be on the narrower side where a slither of my big toe protrudes out, although I would say this did not cause any reduction in performance. Also as mentioned, try before you buy.
Not having worn Nike for a while (since the Alphafly 1 and Vaporfly Next% v1), I can’t compare how the ZoomX in the SF2 performs against other current Nike offerings, but it definitely is softer than the FFTurbo+ in the Asics Metaspeed Paris and perhaps only slightly softer than the Lightstrike Pro in the Adidas Adios Pro 4.
The softness of the ZoomX is stabilised by a full length carbon fibre FlyPlate runs close to the ground at the forefoot before rising to the middle of the midsole at the mid to rearfoot. The curved shape of the plate is apparent via the cutout in the midsole on the lateral side in the forefoot. As to whether the plate’s shape is the same in the VF4, this is unclear.
Weight saving is the name of the game for the SF2 with an aggressively tapered midfoot and an extensive cutout through the length of the midsole foam that exposes the full length FlyPlate. To add to the flexibility promoted through this cutout, I noticed that the FlyPlate flexes very easily. This also was the case in the SF1, which Ryan reviewed back in 2022. I particularly like this, as the ride is more forgiving and it feels a lot more natural to run in, like a traditional flat but with the assistance of a plate. Compare this with the Asics Metaspeed LD, which is a long distance track shoe with an integrated carbon spike plate, there is absolutely no flex offered.
Finally, and also as touched on before, the apparent zero to negative drop of the SF2 is definitely noticeable where heel striking is not an option as you would lose all efficiencies created by the rockered / curved forefoot geometry and the FlyPlate’s assistance. To do so would be to work against the shoe itself.
Ryan: This shoe feels worlds apart from the current Vaporfly. The signature characteristics of ZoomX are still present, but in a drastically reduced and narrower-feeling stack. You get a sufficient amount of cushion here to keep your legs from undue soreness, but don’t expect anything like the depth of midsole you get from a Vaporfly. As a result, the Streakfly delivers lightning fast turnover and lower ground contact time than a typical super shoe.
In my review of the Streakfly 1, I noted that while the ZoomX midsole was “spunky without getting overly sloppy," the key drawback was the short midfoot shank that left the shoe feeling "a bit underpowered, especially at toe-off." I described the forefoot as lacking a lengthwise plate, which meant it couldn’t do much to aid in accelerating you forward during the toe-off phase of your stride.
This provides a strong point of contrast with the Streakfly 2. The new full-length carbon Flyplate directly addresses this core issue. While I found the Streakfly 1 felt like a "wet noodle when you really tried to put the power down," the Streakfly 2's stiffer plate provides a much more responsive and powerful ride, making it a huge step in the right direction.
The Streakfly 2 pushes low inertia and responsiveness to the extreme for a road shoe. You also feel much more in tune with the surface you're on, thanks to the minimal material usage, low stack height, and semi-flexible plate.
This makes the Vaporfly a far more versatile, approachable, and easier-to-recommend option. The Streakfly, in contrast, has a very focused and limited use case.
Outsole
Not much can be said about the outsole when there’s, well, not much of it, except that it works well when used according to its intended purpose. As in the images below, only the forefoot has extensive outsole coverage, and even then there is a sizable cutout on the lateral side where a Swoosh has been added. Note that the cutout is exposed ZoomX foam, as are the white unpainted bits between the webbed outsole design.
As in the image above, the webbed outsole pattern is textured for extra traction, with density increasing as you work your way closer to the extreme forefoot. In the image below, and akin to the SF1, two very thin rubber pieces have been placed in the rearfoot. I presume the purpose is to provide some protection for the exposed ZoomX foam. I am not so sure this works as there is considerable wear of the exposed foam where the image below was taken after one 4.5km track session where the SF2 has not seen contact with any concrete or bitumen. I am genuinely intrigued but also fearful as to how long the shoe will last if it is used for ‘road racing’.
Ryan: I share Bryan's suspicion about the outsole's durability. In the Streakfly 1 review, I described its outsole as having a "large slab of black rubber" at the forefoot with "wave-shaped ridges" and a standard double patch of white rubber at the heel. I found its grip "inspiring...on dry surfaces" but "less than perfect with a bit of water on the road."
With the Streakfly 2, it again feels phenomenally fast and grippy when new and on dry surfaces. However, a new point of comparison arises from the concern about the durability of the Streakfly 2's outsole, specifically the prominent, squared off nubs in the forefoot.
I'm fairly confident that these nubs, as well as the heavily exposed midsole, will degrade quickly on asphalt. This will likely affect performance over time. It's best not to go into this one with high expectations for durability, but it serves its purpose well for a shoe intended for lower mileage.
Ride, Conclusions and Recommendations
Bryan: Five smiles for what a unique, bespoke and special shoe the SF2 is and how epic it is when used for paces under 3:15/km (~5:14/mile) which is the sort of pace I can hold for 400m and 800m reps. It felt even more phenomenal at quicker paces and evidently so when I was doing 300m reps at around 2:45-55/km (~4:35/mile) where the ZoomX foam and FlyPlate really complements each other to provide for smooth toe-offs and quick transitions. However, at ‘slower’ paces below 3:30/km (~5:38/mile), the SF2 felt almost dead in the sense that it felt like a raw old school flat. I presume this is where I start to midfoot strike and fail to utilise the forefoot of the shoe, which makes up 99% of what the SF2 is all about.
Unlike its predecessor, the SF2 is not at all approachable in its geometry, stack height and drop (in today’s market and attitude towards this). While it rides fantastically at pace, it does not have the build quality for any sort of every day running, including warming up before a track session. This makes the SF2 a very specific shoe for specific uses only. For runners like myself (18 minute 5k, sub 3 marathon runner), I will only take the SF2 out for specific quality sessions, and not even for fartlek or threshold sessions. If there was a little more stack in the heel and outsole coverage, I could see myself using the shoe so much more.
My final thoughts are that the SF2 would be a competitor to the Adidas Takumi Sen 10/11, but it also is not as the TS is far more versatile. It is also like the Asics Metaspeed LD, but is technically more versatile as the SF2 can be used on the road. But the question is, would you?
I love the SF2, but I have scored it down for value as being such a unique shoe, it does not offer that much value for money due to its lack of versatility. Perhaps if I were a track athlete or a much faster runner, I could see myself scoring it a lot higher.
Score: 8.9/10
Ride 9 (50%) Fit: 10 (30%) Value: 6 (15%) Style: 10 (5%)
😊😊😊😊😊
Ryan: I agree with Bryan's take on the shoe's versatility; it feels unnatural and inefficient at anything less than a hard effort. This is, without a doubt, a significant improvement over the first version. It's now a shoe I would consider for any track reps up to a mile in length, but it shines brightest during training reps of around 400-800m (if I were 10 years younger and still capable of 'spiking up' without near-certainty of lower leg injury, I'd still prefer spikes for racing).
For anything a mile and up, the latest Vaporfly is still so good that it remains my preference.
If you are looking for a shoe to carry you through high-intensity workouts on the track, I would be inclined to recommend the Streakfly 2, provided you are not a heel striker. However, if you value bang for your buck, durability, versatility, or an approachable ride, I would recommend the Vaporfly hands down.
Fit is true to size, although it’s worth noting that because this is a racing shoe, it's narrower and hugs more tightly than does a trainer of the same size.
Score: 8.7/10
(Deductions for low versatility and narrow use case, questionable durability)
😊😊😊😊
7 Comparisons
Adidas Takumi Sen 8 (RTR Review)
Brayn: On paper the TS is the shoe most similar to the SF1 and SF2, as both TS and SF are intended to be shorter distance road racing shoes. However, I think the TS is more suitable to this purpose. Whilst the TS8 is no longer as relevant, the upcoming TS11 appears to be an exciting update to the TS lineage. It appears that the TS11 would be a ‘lite’ competitor to the VF4, and the SF2 is a ‘lite’ competitor to the TS11. It seems Adidas and Nike are a little off calibration in their carbon plated line up, with the former having the TS10/11 for shorter distances, the ever versatile Adios Pro 4 for all other distances, and the illegal (stack height wise) Prime X Strung 3, and the latter having the SF2 for shorter distances, the VF4 for distances up to the marathon, and the Alphafly 3 as the flagship marathon shoe. Does the TS compare with the SF2, I’d argue no as the TS is far more versatile and able to be worn by many more more meaningfully.
Ryan: I'm in agreement with Bryan again here. The Takumi is the more versatile pick, and I think it is still just as capable as the Streakfly at short, hard intervals. I tend to wear the Takumi (which hasn’t changed too much from version 8-10) for faster track workouts, thanks to its dual talents of providing snappy turnover and keeping my legs from feeling too banged up the following day. The Takumi’s lockdown is just as tenacious and sporty as that of the Streakfly. I also find the Takumi to be more stable and energetic than the Nike. For those reasons, I’ll consistently pick the Takumi over the Streakfly.
Asics Metaspeed LD
Bryan: At 4.2 oz / 119g in the LD, this is only one of two pairs of shoes I have worn that is lighter than the SF2. But can the LD be considered a running shoe given that it can actually only be used on track? The LD (not version 2) was released in 2023 and retailed at AUD 400 (250 USD), and was essentially the track version of the Metaspeed+, with a FFTurbo midsole and an exposed fully rigid sculpted and integrated spike plate which meant that no spikes were actually needed. The LD is intended for track races up to 10,000m. Whilst less forgiving than the SF2 in the forefoot due to the rigidity of the spike plate, it is actually more versatile as there is a perceivable drop and the shoe allows you to midfoot strike and also where the spike plate commences in the midfoot (see image below). The FFTurbo is noticeably firmer as it is nylon based and not Pebax. The SF2 is softer and is also ‘capable’ of being used off track. Similar to the SF2, the LD did not receive much, if any fanfare upon release due to is extremely limited audience.
Reebok Floatride Run Fast Pro 2 (RTR Review)
Bryan: This is the only shoe I have worn that is significantly (mind boggling to use this term) lighter than the SF2, coming in at 3.88oz / 110g. It too utilises a PEBAX only midsole, but does not have a plate. The RFP2 has a lot of ground feel and has ample flex, as it has no structural aids in its construction. Whilst you can say it is a lot more versatile than the SF2, it really isn’t, as it too is calf destroying given its very minimal construction. THe RFP2 and SF2 are shoes I will only take out at quality track sessions. The difference is that with the RFP2, I can take it on the warm ups and cool downs as well. Each is unique within its own rights.
Asics Sortie Magic 6 (RTR Review)
Bryan: The SM6 and SF2 also weigh the same, but the SM6 is a traditional flat with no plate, and rides even lower at close to 20mm in the heel. As a traditional flat, the SM6 has far more ground feel and requires you to generate the power with no assistance. The SM6 would also be more durable with its full outsole coverage and in particular has a better traction with a DSP waffle outsole in the forefoot. The SF2 is however the faster shoe.
Adidas Adios Pro 4 (RTR Review)
Bryan: I have thrown this in as an almost tongue-in-cheek comparison. The AP4 is the total opposite of the SF2, as with other max stack plated supershoes. I compare the AP4 because it is a shoe I would be willing to wear for the marathon, but also at 800m and mile repeats at 3:30/km (~5:38/mile). In terms of versatility, the AP4 is the complete opposite of the SF2. Where I would use the SF2 is for a track race if I were to enter one, and quality repeats. But for a 5000m track race, I would actually pick the AP4 over the SF2.
Ryan: I think Bryan nails the major idea here: the AP4 is much more versatile of a shoe. While the Adidas is slower to turn over and not as snappy on foot, it’s still highly capable, and the shoe I would prefer for all but the hardest, shortest efforts. The Streakfly has a far more aggressive and racer-like fit, but doesn’t have anything like the energetic bounce and impact protection that AP4 offers.
Hoka Cielo Road (RTR Review)
Bryan: The Cielo Road offers an interesting contrast as another shoe aimed at shorter, faster efforts but without a plate. The Cielo’s PEBA-only midsole is playful and approachable, but can feel wobbly and underpowered at times, especially in the heel. The Streakfly 2, with its new full-length FlyPlate, feels significantly more stable and powerful at toe-off. While the Streakfly 1’s flexibility was a major drawback, the Streakfly 2’s added stiffness gives it a clear performance edge over the plateless Cielo Road. The Hoka doesn't feel like it's as serious of a racer with a relatively lax foot hold, and not as quick of a turnover.
Nike Vaporfly 4 (RTR Review)
Bryan: This latest Vaporfly iteration has become more versatile and, in my opinion, creates more separation between it and the Alphafly. While the Alphafly is now more distinctly the long-haul marathoner, the VF4 feels more like a jack-of-all-trades for distances from 5k on up. This is where it contrasts most with the Streakfly 2, which has a much narrower and more specific use case. The VF4, despite a reduction in stack height from its predecessor, still feels substantially more cushioned and protective than the Streakfly 2, making it a better choice for longer races or runners who want more forgiveness.
The Streakfly 2, with its lower profile and aggressive feel, is a pure speed-oriented shoe that excels in short, intense efforts and track work where low inertia is paramount. The VF4, while incredibly light and nimble itself, offers a more balanced ride that doesn't demand the same level of forefoot-focused running. If you want a shoe that can handle a 5k as well as a half-marathon with a more traditional super-shoe feel, the Vaporfly 4 is the clear choice. If your focus is purely on short, fast reps and a ride that feels like a spiked shoe made comfortable for the road, the Streakfly 2 carves out its own unique niche.
Index to all RTR reviews: HERE
Tester Profiles
Ryan Eller A hopeless soccer career led Ryan to take up running, and after taking a decade-long break from competing, he is back racking up mileage whenever he can. He calls the 2018 Boston Marathon the hardest race of his life, where he finished in 2:40, barely remembering his name at the finish line. Rya more recently has a PR of 2:14:23 from the 2024 Boston Marathon finishing 3d American and 15th overall, a 2:17:16 Olympic Marathon Trials qualifier, from the 2023 Philadelphia Marathon after two other 2:18 efforts in the last year.
Bryan Lim lives in Melbourne, Australia. He picked up running in mid-2016 as a stressed-out law school student and ended up running a full marathon as his first event. Ever since, he has focussed on becoming a better runner, with PRs of 1:22 in the half-marathon and 2:59 in the marathon. Bryan also enjoys longer distances and trail events, and has run the 2024 Comrades marathon in 8:05 and a driveway ultra (52km over 838 laps) in the midst of a Covid-19 lockdown. He also enjoys running tourism, completing the Chicago Marathon, Amsterdam Marathon, Shonan Marathon and Toronto Half. Whilst enjoying running, he has taken the community aspect of things with passion. Bryan is an accredited Athletics Australia community coach and runs his own local track club, Glasshouse Run Club.
The Streakfly 2 was a personal purchase for Bryan and a free review sample for Ryan. RoadTrail Run has affiliate partnerships and may earn commission on products purchased via shopping links in this article. These partnerships do not influence our editorial content. The opinions herein are entirely the authors'.
Europe only: use RTR code RTR5ALL for 5% off all products, even sale products
No comments:
Post a Comment