We Went to a Wind Tunnel to Build the Fastest Unbound 200 Bike and This Is The Result

[@TheRflynn]

You’ve changed Dylan Johnson. Before your big name sponsorship you were a simple, straightforward, single-minded almost obsessive gravel racer. Now you’ve become a simple, straightforward, single-minded almost obsessive gravel racer with a budget.

[@casper5204]

I see this as a neutral change?

[@TheRflynn]

@@casper5204a bonus!

[@elonif4125]

@@casper5204Its sarcasm

[@theorangehelmetguy]

haha sooooo true

[@SpicyTrifongo]

the spirit of gravel is truly dead.

[@RhettShull]

I’m not fast, I’ll never be fast…but I will put deep road wheels and XC tires on my gravel bike because it looks rad as hell.

[@d-vngwenya4043]

Just the anxiety and disgust from roadies is worth it

[@MrRafaztar]

Im fully expecting you to have a bike collection to rival the guitar collection 😉

[@lexington476]

And half of cycling is looking cool 😎.

[@PatrickWarren-b4i]

⁠@@d-vngwenya4043

[@blaw7717]

@@lexington476 And the other 60% is feeling fast..

[@cyclingcalifornia510]

10th place elite. I think that proves all this was worth it.

[@tt-tk9076]

WE GETTING 16TH WITH THIS ONE BABY 🗣️🗣️🗣️🔥🔥🔥🔥™️

[@tt-tk9076]

wait dude actually said it LOL

[@grantpostma]

What a banger

[@jamiewilkinsracing]

Savage

[@shimona500]

Matej bumps him to 17th

[@davehause8571]

Hahah. Only thing worse is all the overweight amateurs doing the same thing.

[@pierrex3226]

Best 17th rider gravel bike EVER! LOVE your work.

[@oscsun]

This half hour bike check could easily have been twice the length, can't get enough of this type of Dylan content! :D

[@n8torious309]

" On a dry course, these will be the tires I run on race day" The weather: I'm about to ruin this man's whole career

[@pepelkors]

rainy just like last year :)

[@waisinglee1509]

Hahaha

[@Team_TACTIC]

This didn't age well

[@topotu_7473]

Turns out it did in fact not ruin his career 😅

[@RoadHardened]

This video is so dope. The fact that you share all this information on the internet for us and even your competitors to see and use for free is amazing. Thank you. An absolute no-brainer like and subscribe!

[@suisinghoraceho2403]

If spirit of gravel ever existed, this is it.

[@Keksator]

the fact that you finished 10th with that increasing competition you talked about is epic, congrats

[@honestreviewer3283]

Just wanted to congratulate you Dylan for finally being recognized amongst the elites of gravel racing. Years of hard work is paying off!

[@Heliosmaster]

Request: next time also a total watt savings? Optimizing each component individually doesn't necessarily mean the package is just the sum of the savings.. but would be nice to see a "baseline everything" with your final setup.

[@glebsorokin]

+

[@davehause8571]

I'd like to see the wind tunnel savings with the rider ACTUALLY pedaling during testing.

[@philipegoulet448]

​@@davehause8571I understand why you would want that, but I think it would significantly complicate getting consistent results, which is absolutely crucial when you are measuring 0.1w differences

[@dhengen]

Perfectly designed and built to get 17th!

[@christophertan3195]

17th out of a thousand lol

[@kennethv2340]

​​@@christophertan3195about 147 actually.

[@gcanzano36]

THE FIELD KEEPS GETTING STRONGER

[@dtibor5903]

Extremely good achievement to be 17th. And how do you perform in races?

[@dhengen]

@@dtibor5903 Not as good! Are you familiar with Dylans own joke about always coming 17th? It was only a reference to his own comments. Relax, I'm not out here hating on anyone.

[@jonathanrobinson2628]

I'll be the first to admit that I don't get the appeal of Unbound, but I have enormous respect for anyone that takes it on. Our Scandinavian gravel is quite different; arguably more enjoyable, but the pure grit, power and fitness required just to complete Unbound is remarkable. Well done for the result and also for thinking so much about the set up. Innovative bike set ups can make all the difference.

[@Bob_Shy_132]

i dig the fact that you went full experimental, geek mode on this. One thing that you may have overlooked about the fork is that your neck, shoulders, elbows and wrists will be less fatigued making your body feel less worn out. Sidenote: More mass (weight) at speed is a little easier to keep moving at that speed. Light weight is better for accel / decel.

[@JackMott]

"More mass (weight) at speed is a little easier to keep moving at that speed." That is a bit of a misleading thing to say. If you are moving at 25mph and stop pedaling, then yes a heavier bike/wheel will slow down at a slower rate. But it does not reduce the power needed to hold 25mph, at all. But generally the penalty on acceleration of extra mass, even wheel mass, is much less than people tend to worry about. Cyclists just don't accelerate hard enough, nor are typical mass differences big enough, for this to be a significant factor.

[@shawnnong5999]

More mass is not easier. Increased rolling resistance power loss

[@michiganstate149]

I'm surprised more people don't talk about this. Comfort is key.

[@Bob_Shy_132]

@@JackMott My impatience forgot about inertia.

[@mtndogdad]

imagine being in 16th place seeing this 28lb rig coming up on you in the final miles...

[@valiantabello]

OUR BOY GOT TOP 10 @ UNBOUND!!!

[@SamuelBlackMetalRider]

The type of Content we absolutely LOVE while we’ll never ride UnBound 200 ever

[@perserventia]

Awesome. I'll be there but not racing - I will be support team for my daughter doing her 4th Unbound. Hope to see that bike and you on the podium!

[@clinlashway9147]

As an engineer, I like that form is following function here. I love the wide tires on the deep rims. Concerning crank arm length, I'm 6' 2" and switched from 172.5 to 165 mm cranks this year. All up side. Knee pain resolved. So, I'm not surprised that at 5' 10", the 165 mm cranks are working for you.

[@GarbageLegs]

I'm 6'5 and use 165mm cranks on my TT and road bikes. The only downside is in fit when you need to raise your saddle to compensate and now you've got a larger saddle-bar height differential, which might bother some people.

[@leojosephy]

@@GarbageLegs I wonder if the aero is worse with the higher saddle height, or better with less leg travel, or same same.

[@shred3005]

I’m 6” and ridden 175mm cranks on road and gravel my entire adult life. I’m 59. Given all the enthusiasm for shorter cranks, I’m thinking of giving 165mm a go for my gravel bike even though I’ve never had knee issues

[@ProWeAreSo]

I’m 5’10 and switched to 160mm on the new ultegra cranks from 165 (and from 172.5 before), and there’s been no difference in power output but I’m way more comfortable

[@3TZZZ]

@@shred3005 As above, you’ll need to raise your saddle by 10mm, which might affect your lower back angle. But then it might also improve your hip angle. I’m 55 and 6” and I recently changed from 172.5mm to 170mm cranks and even that is noticeable in the lower back due to the slightly higher seat height. It’s an interesting equation for a bike fitter to answer.

[@Baggellyh]

Insane stuff, the detail here is incredible, peak cycling YT content

[@aaronhamlen8215]

Thanks Dylan, I have used the Race Kings for years with no flats on my mtn bike. Good luck at Unbound.

[@paddlestandingup]

Complete monster truck vibes. Just need some way to shoot flames out of your hubs. Looks very, very cool. Love it.

[@perserventia]

Super Congrats on your 10th place finish!! In THAT field, WOW! You demonstrated that You are a serious Contender 🎉

[@pinolav]

Congratulations for your 10 position on the unbound wwwooowwwwww crazyyyyu

[@jas_n]

The bounce you get out of your tires @4:20 when you first get out of the saddle is....incredible

[@CleverSmart123]

Congratulations on this amazing result!! I followed the livetracking of the race and was so hopeful that you your get a new best result. Well done!!

[@danielsekera3525]

I'm laughing literally out loud at all the people making comments about 16th and 17th and thinking not one of these people are posting THEIR race results it is amazing, even gravel has its tools and fools. Love the content Dylan.

[@JoshuaTootell]

I finish near last in my big events and I'm stoked. Line up against the best in America and see how many people go home 😂

[@rlm4471]

I think it's mostly just good-natured fun. Most of us know that Dylan is very fast and talented, and that we don't have what it takes to perform at his level. 16th or 17th is a huge result at Unbound.

[@AaronShaffer-ky3ve]

Well-done. I appreciate the thoroughness that you went through to optimize the bike for Unbound. Reporting on your wind tunnel data made those insights accessible to everyone - thank you!

[@davidalhoff7190]

Cool preparations as fluid mechanics engineer I must say amazing great and detailed study. As a cyclist, I must say I am so jealous;) Have fun and good luck at the race!

[@andrewsher1]

The result speaks for itself. Congratulation !!!!

[@ThePowermax01]

Here before the post race recap "I did my highest NP ever and managed a top 20, the field is just so much stronger than last year" I'll be watching it tho! Good luck at Unbound!

[@Dustydayzz]

but how is that a fail?

[@ThePowermax01]

@@Dustydayzz who said anything about a fail?

[@AndrewJamesBowen]

Top 10 so good. Can't wait to see that finish

[@Dustydayzz]

@@ThePowermax01 you implied it

[@ThePowermax01]

@@Dustydayzz I couldn't get a top 20 at Unbound, even less finish 10th. Not sure where you're coming from, might be your first time here

[@aarondcmedia9585]

Congrats on a fantastic result - the bike worked!? well the training did definitely. Well done. Looking forward to the recap with much anticipation.

[@christianemeiners9224]

🤓 Nerds at work, love it🙌

[@davidlitt4246]

Congratulations. Awesome ride at Unbound. Look forward to the report!!

[@CleverSmart123]

Lovely bike and setup, perfect for my half hour tour in the woods in flat terrain.

[@matthewjam3s]

Can’t rate this channel enough. For those of us into bikes, nutrition,marginal gains, all of the above, it’s amazing. Also, it’ll be interesting to see how this bike fares and compare it against your numbers/performance. Hopefully your physical performance is at its peak so bike performance can be compared to previous times. Thanks for the hard work that goes into this!

[@alexanderakins5777]

Took forever to come out but I’ll forgive you cause I LOVE these aero videos, I’m the guy who gave u those aero bar ends at sea otter with the wild 32cm bar road bike. I also have the solution to the elbow flare out on narrower bars if you’re interested.

[@johnmooney3923]

Don’t be bashful, let’s hear it

[@brijlunine6416]

Congrats on your excellent result. Looks like your set up paid off--along with all the training!

[@BuexxTM]

if you freeze the bottle down the chest its also keeping you cooler for longer. So win win win

[@billpickle2875]

What an amazing result! Top 10 but against a much tougher field. Insane progress. Cant wait for the video and thoughts on this one

[@rsrnsrwds]

Very interesting set up. Dylan boldly breaking the mold and going for it! Best of luck!!! Will be looking forward to your race report.

[@SandSanta]

I ran the conti race kings in my past gravel race this weekend based on this video and while I'm no elite racer - those tires chewed up the terrain. The descents especially were comfortable and confident allowing me to go measurably faster then when I had 45mm gravel tires. Would love a video on tire strategy alone.

[@orazuara]

Congratulations for your 10th place!

[@KelvinSuddith]

Interesting listening to the discussion of the airflow over the deeper rims. It never ceases to amaze me how almost all things that mimic the shape of a raindrop are faster than things that are less similar. Deep section wheels add the same tail shape that raindrops form

[@matthewfoote12]

I wish Dylan would talk about this... Why not custom 3D print a lightweight ABS fairing behind the fork (70g), then use a fairly affordable carbon mold on that fairing to get it down to 20g? This approach gives you all the control in the world with airflow, especially if you're running deep section rims to control the airflow and pressure zones around and in between the rim. Using the fork fairing to help direct airflow and make the flow more laminar. The airflow would be more controlled, and a fairing coming off the back of the fork would help break the airflow for the leg as well. It might sound crazy, but I've been experimenting with this using a flat out-and-back course and my own 3D printer on a Fox 32 fork, using the rule of 105 for aerodynamics. It seems to be quite effective. I haven't heard much discussion about this, and maybe it is against the rules, but for NICA races or local events, it seems like a fun way to gain a decent advantage. Another pro tip is to use 30-inch stretch wrap for your inner triangle on non-crosswind days to gain a few watts at almost zero weight. If you want to take it a step further, you can even use 30-inch stretch wrap on the wheel (I know it sounds insane, I should make a video on it) to create ultra-lightweight disc wheels for your MTB. You can then directly attach the stretch wrap to Continental Race Kings, getting far closer to the rule of 105 than you otherwise could. It sounds silly, but it actually works incredibly well. The adhesive is so strong that if you clean your wheel with isopropyl alcohol first, the adhesion is insane. It lasted me 112 miles with no issues on MTB trails, including going off small jumps. Recap: - 3D print a fairing behind the fork and behind the seat post (using the rule of 105) to reduce drag, and even use slight dimpling to artificially change the Reynolds number. - Stretch wrap your inner triangle with one-sided ultra-adhesive stretch wrap (30-inch). - Stretch wrap your wheel with one-sided ultra-adhesive stretch wrap (30-inch) by taking off your cassette and disk first, then applying it directly to the wheel to make the whole thing one piece, covering the entire diameter. - Use small silicone dimples on your race day skin suit and aero shoe covers or aero socks to reduce drag, applying them in a similar pattern to the Endura Encapsulator for best results. **Links:** - Match this pattern: [Endura Encapsulator Suit](us.endurasport.com/d2z-encapsulator-suit-ssthiviz-blue/12926217.html?affil=thggps&switchcurrency=USD&shippingcountry=US&variation=12926218&gad_source=1&gclid=Cj0KCQjwpNuyBhCuARIsANJqL9O54DhlKA-hgmU1Y4ib2DjuZBT1IMcJDKROYMr_7SI_6txHMP1O5oEaAtN6EALw_wcB&gclsrc=aw.ds) - Use these stickies: [Glue Dots](www.uline.com/Product/Detail/S-10366/Glue-Dots/Dot-Shot-Pro-High-Tack-Low-Profile-Glue-Dots?pricode=WA9090&gadtype=pla&id=S-10366&gad_source=1&gclid=Cj0KCQjwpNuyBhCuARIsANJqL9M86ZJXxyqrCnzWCngzsyD_7zsmRvArTltAHnmJfPHky03y94DCUdwaAkZDEALw_wcB) - Use this stretch wrap: [Stretch Wrap](www.uline.com/Product/Detail/S-17973/Stretch-Wrap-Machines/Portable-Stretch-Wrap-Cast-80-gauge-40-x-5000?pricode=WA9377&gadtype=pla&id=S-17973&gad_source=1&gclid=Cj0KCQjwpNuyBhCuARIsANJqL9OcLljqRsQZMWfAlTQi77WnFDtscf8tzen4D1Xwvcu3FNC7w9iYMZwaAgNWEALw_wcB) I can share the 3D modeled STL files for the fork if you want. They are currently modeled for Fox 32 and 34 forks and RockShox forks. The models perfectly mold around your disk brakes as I 3D scanned the forks into Fusion 360 for CFD testing. I am currently on my 8th model and making huge gains in fork design. I am also working on a forged carbon layup mold to reduce the 3D print weight significantly, so I can manufacture them for some of the kids I coach. I know Josh from Silca hates the whole fairing thing and tall aero socks, but it just feels fun to go faster and know you have an advantage over the competition.

[@treszenrv9401]

fairing is forbidden buy UCI rules

[@matthewfoote12]

@@treszenrv9401 Unbound isn't a UCI race though is it?

[@towhee7472]

I'm a simple man. I see Dylan run Conti Race King, I buy Conti Race King.

[@midwesttreasureandrelicrec7914]

But the caveat is do you run 60 mm deep road wheels? Change the wheel configuration that could all go out the window

[@darrendondero520]

Can you give a link to the exact Continental Race King model? There seems to be a number of variants.

[@rfwillett2424]

I hear the Conti Race Kings are in short supply, I wonder why?

[@808threadripper6]

​@rfwillett2424 hahahaha dylan talks about race kings everyone purchases them. Next time he may want to throw out pathfinder pros and when the race is over tell everyone he was on conti... although I love that he is so transparent with us on his setups and training

[@Zyzzyx42]

A bit thrilled to see that info for the Lauf fork. Been enjoying mine for about a year now. Though I cruise closer to 20kph instead of 20mph, so not as worried about the aero. The comfort though, it rocks. And I'm also running a 55mm tire. So nice.

[@zimmejoc]

congrats on 10th place. Tell BHD to suck it; you moved up 7 places. Can't wait to see your vid about the race.

[@horststorkebaum6475]

Good luck for Unbound, Dylan! I hope you get through it unscathed and happy with your result.

[@jamescarlphotography4523]

I’ll give you props for even testing the Lauff fork. Old school intuition wouldn’t have even considered it.

[@tripleb7232]

Congratulations Dylan on your 10 place finish!!!! Bravooo!!!

[@veganpotterthevegan]

I love the Lauf fork on my hardtail. But I am surprised that nobody is making an aerofoil air suspension fork at this point. I get that this tested faster but the round tubed forks have no thought of aerodynamics put into them at all.

[@theorangehelmetguy]

I'm here for it! Get a great results and watch everyone start heading in this direction. I love your creativity with this type of stuff. I CANNOT wait to see how this goes!!

[@Benno828282]

Amazing 10! Well done

[@marvinkamei7007]

what about adding full coverage fenders and min tire widths?? Areo fenders like a fairing!!

[@BlackWaterCyclist]

Great video! Really enjoyed geeking out on all of this! 165mm cranks for the win. I always tell my clients who are below 6 ft to try shorter cranks. I myself have tried 155 up to 190 crank arms and the shorter are always more comfortable and if it allows you to ride more, then you can train more.

[@JoshuaTootell]

5'8" and I have less discomfort on 175 cranks compared to 165.

[@BlackWaterCyclist]

​@@JoshuaTootellI definitely do not feel it is all about leg length either. In my opinion it has more to do with flexibility, not just of the legs but back, shoulders, and neck. Also depends if you are a heel dropper vs toe down Pedaler. There are so many variables but for most, shorter is better.

[@peteransel2715]

Drool worthy! Thanks for sharing so much info! I'm always learning from your videos. A lot of racers wouldn't share these tricks. Cool that you do!

[@nomadtrails]

So ready to see the Lauf fork on Dylan's bike!

[@robbchastain3036]

Thanks, Dylan and Silca, for wind-tunnel results of various tire and wheel combinations. And big picture, gravel is looking more tri with every big race, without the aero bars, happily, not a fan of those on dirt. I'm cheering for you, Dylan, and everyone else contending for 16th place, not that I want anyone taking your place, Dylan! Have fun, be safe, aim high! 😀

[@hmudesign]

What an excellent and no nonsense video Dylan, best of luck in your Unbound race, top 10 :)

[@hmudesign]

And top 10 it was!!! Congratulations Dylan, this was amazing!! ❤

[@jamescaldwell5]

I tested the first Lauf fork at Las Vegas Interbike many years ago, and LOVED IT. I was sad that I did not have a bike to put it on at the time or I would have bought one at the show. I have a fantasy gravel build I have been thinking about that includes one of those forks, I am very excited to hear that along with all the other benefits its also very aero.

[@joegerdes3942]

Missed my group Ride because of this Video 😢 100% worth it

[@mateagoston8145]

Worth it, I am also not very keen in spending time with my local BHDs instead of educating myself. :D

[@dorothyb.]

10th 🎉 Dylan Johnson you absolute star 🌟. The form, the set up , served you well

[@kevinderung8524]

I can't imagine anyone does more work in setup and training than this guy?

[@rlm4471]

Keegan does a ton of testing. Doesn't post videos about it, though.

[@carltonpowers2342]

Saw the Lauf bike on GCN when Alex and his wife did Big Sugar. I ride an older F85, and want this fork to add some comfort without sacrificing performance.

[@JonathanHair]

The worst thing about gravel racing is the terrible number plates.

[@l.d.t.6327]

I was going to say that his man-on-the-bike wind tunnel testing is an absolute waste of time without the number plate attached.

[@future62]

@@l.d.t.6327 Yea there's absolutely nothing to be learned w/o the number plate

[@jimsonjohnson3761]

It so dumb. Just unprofessional for actual racers. Just use the jersey tags what the hell is wrong with that?

[@l.d.t.6327]

@@future62 In Dylan's defense: it's not 'nothing' to be learned as fork / wheels+tires... is still important and thus useful info. It's ofcourse a shame any marginal gains are compensated by that number, but that is what it is. I bet some people will still try to fold / cut parts of the number.

[@robs6750]

Unbound should go with the timing chips that attach to the fork instead of the chips on the back of the number plate, at least for the elite riders

[@ElectricGhostOpera]

Amazing effort at Unbound!!! Hard work and dedication pays off! Congratulations!

[@robmessmer6366]

Justified, Vindicated, Proven, I don’t care what word you use but our boy Dylan just proved to any hater/doubter that marginal gains, thinking outside the box, and trusting science not fashion = speed. No offense to Dylan’s “talent” (genetic potential), but there were so many dudes on the start list with higher meathead ftp’s. And while Dylan probably has excellent off-road skills, his commitment to courageously adopting gains despite its cool factor (insert Lauf fork here) was 100% proven on Saturday. Despite the budgets Specialized, Cannondale and other major brands make into engineers, wind tunnels, R&D, it’s now apparent that a skinny boy from NC with a split-personality (Dylan & BHD) who simply knows how to read, dominated them all (measured in Talent-to-Placement). It actually makes sense why, these big brands not only need to find the science but their business models depend on if it looks fast, cool, or is fashionable. Dylan clearly likes a cool look, but you know what is a higher priority for him, unadulterated SPEED! Unattached to a tire sponsor, Dylan has been the people’s Tire Whisperer, now a big bike brand need to wake up and hire him onto their R&D team, I’m not kidding! Dylan could literally change a brands trajectory that speed is “cool”. I guarantee you that Lauf will see gravel fork sales explode. I’ve been following Dylan since his pimple faced early videos, and I’m so proud of his determination and that he’s making us faster, Saturday will go down as Dylan Johnson Day! All hail the Tire Whisperer.

[@lidarman2]

Congrats on tenth finish in Unbound. Looking forward to your take on it. Saw the Veloworthy report and it was outstanding...Looked like you had a great time. No mud field!. Cheers.

[@stephenlarue6842]

Bad ass!! Top 10..!! Congrats!!!! Great ride!!!!!!!

[@kevingregoire1042]

honest and pretty transparent review. All interesting. Great race perf also. Keep it up ;)

[@guykrige812]

Massive congratulations on a fantastic result in Unbound ‘24! All your hard work and SCIENCE paid off! Super impressed. Well done Dylan

[@Cary-cy1fy]

I am so retro, but this channel has so much good content. Congratulations on a fine race, and thanks for making this sort of tech umderstandable to simple minded people like myself

[@crypto_que]

Dylan: Bottle down jersey Me: "3 Watts" Dylan: FIVE WATTS 🤯

[@ragnilw]

WOW awesome result. Well done. seems that 17th curse is broken

[@dkeisj153]

Another great video Dylan! I always look forward to and enjoy them! I really enjoy and appreciate the nerding out you do. Did you see the same areo gains with the wide tires and deep rims for various amounts of yaw (or will you only be going straight :) )

[@Adam_Aundra]

Was wondering the same thing, loved the video but it would be nice to have access to the data he collected.

[@kevinbarkema1666]

Congrats on the top 10. Really excited for the next Bonk Bros podcast

[@xuchenglin6256]

A lot of people forget that bigger tyre is also taller. With a tyre this tall, it's no longer an light bulb with an trailing rim, but the side wall of that tyre itself should be considered some kind of "rim". You should probably think the first 1/3 of that tyre as the traditional light bulb but the rest 2/3 actually a perfect 105% rim. I suspect this a long time, as when you see from a distance, from the sideview, an MTB tyre with an MTB wheel looks just like a deep section road wheel with road tyre. Of course this is just my speculation, to get an answer for this, you might try go the CFD route, because the CFD has the advantage of giving you a full scale idea of what's going on at every part of the system, instead of the wind tunnel just a number without any why. Your testing is kind of ground-breaking. Maybe try to get in touch with some people in the academic circle? Your quest could make an interesting research topic for someone who happen to know how to write a paper.

[@keithnewton1966]

I was going to mention the tire clearance in the peanut butter mud but you had that covered. Data doesn’t lie👍

[@efraer]

Another great video, Dylan. Unusual gear choices for marginal gains, backed up with wind tunnel receipts, is the content I'm here for. Good luck at Unbound!

[@treszenrv9401]

Dylan Johnson M 29 Bib 55B revard, NC, USA 10 21.86 MPH 9:16:36 Look like a nice result. 👍

[@wazzup105]

Good luck at unbound. Can't wait for the race report.

[@harrie974]

If you add up all those savings you are already 15 minutes ahead😉 Good luck on race day, Dylan👍

[@Liimed_]

the video is so interesting, loved it !

[@Frostbiker]

This was ugly, weird, unintuitive and utterly fascinating. Can't argue with results!

[@JC-zc1dq]

well done @DylanJohnsonCycling - 10th place with what looked like a possible 5th place with your gap at the end in the most stacked field ever in unbound. Marginal gains pay off!!

[@tannerminnis6112]

Dylan, another great video. Thanks for stopping by and checking in with the "Shiftless" podcast crew. Great interview. But I have to say I love your crank/chainring/PM setup. Seems like an awesome "hack", and I'm just glad to see other options than a 1x40T ring in the front. Keep up the great work and good luck out there at Unbound! Hope you and Backwards Hat Dylan smash it!

[@ipodgolfer13]

I followed suit with a dropbar converted MTB for a couple of races already this year. Used the racekings as well and it was a solid choice.

[@Bigkidbird4]

Very nice ride

[@alexanderwooldridgesmith6629]

Having run that tyre set up on my XC bike for a few years I can state that they are surprisingly good in mud, the rear has all the traction I want until its time to fit winter knobblies.

[@defiantparsnip]

I can't believe you didn't take into account the greatest marginal gains in gravel racing: the mustache and the mullet. Aero costs? absolutely. But the wattage gains from being the sexiest cyclist out there more than make up for them.

[@derekkuhl]

You did much much better than 16th! Congratulations!

[@You-Tube-jk9wu]

Regarding the relation of rim width and tire width: from a hydromechanic perspective you can’t break it down to a simple 2D flow case and a Karman vortex shedding. As the wheel rotates a lot of axial, tangential and radial velocities are induced. The total flow field gets way more complex as you leave the horizontal plane that falls into the axis of your front axle. Viscous stresses are affected as well. Additional surfaces mean additional viscous drag. How this drag is balanced with the vortex shedding at the spokes can not be answered without detailed simulation. Furthermore laminar-turbulent flow areas are totally different at the top end of the wheel compared to the bottom end, as relative velocities between inflow and wheel are totally different, which again means different drag in vertical direction. Cross flow drag at side wind conditions is affected as well. Compared to aerodynamic wing geometries, thicker leading edges (your tire) lead to higher pressure drag but delays flow separation at the suction side. And there are interactions with fork and frame, as the wheels alter the pressure field on both. You can go on and on. Interesting but complicated topic. Think you nailed it by simply testing it in a wind tunnel. Keep in mind, that the measurement results strongly depend on the environmental conditions, as they shift over (day-)time.

[@You-Tube-jk9wu]

And on the roughness topic: There are structured and unstructured roughness types, that alter the velocity (and Reynolds number) and subsequently the pressure field. See the PHD an articles of my colleague Turnow et al on dimpled structures. The effect of wall roughness can be estimated comparing boundary layer thickness and roughness height. There are three different flow regimes: hydraulic smooth, transitional and rough. But I think that is way too far down the rabbit hole. 😄

[@anotheremailaddress9664]

This guy aeros…

[@glebsorokin]

Excellent and interesting comment! I just wanted to add that using oval bicycle wheels will help in the smooth separation and recombination of airflows, reducing vortex formation and turbulence. The oval shape, elongated in the direction of the flow, has a smaller projection area compared to a round shape of the same maximum width. This means less air needs to be displaced or divided as the object moves through it, which reduces drag.

[@anotheremailaddress9664]

@@glebsorokin I can’t tell if you are pulling my leg., but curiosity has the better. What does an “oval” bike wheel look like? Are you talking about an inner rim shape that is not a uniform inner circumference?

[@joebob1994]

Thanks for giving so much!! Really appreciate it.

[@estelja]

Dylan, any idea where to still get the non-E25 rated Conti Race King Protections? They are slightly faster per BRR site but they kept the same part number so really hard to tell from retailers websites which one they are selling. Which are you using, original or the newer E25's?

[@walshman70]

Great content Dylan! Very interesting insights. Bringing new definition to 'sweating the small stuff'!

[@CameronWilson-qi6pr]

How many watts would a beer belly save over the unbound distance?

[@ASGundogs]

I think GCN have made a very similar video to that question 🤣

[@chrisridesbicycles]

I suddenly feel 10W faster. 😂

[@michaelhatch1994]

I don't race gravel and the widest tires I'll ever have are 25mm, but I love the attention to detail which you bring to the subject. Good luck.

[@matejgorsic7388]

Any particular reason for choosing RaceKings over ThunderBurts?

[@pl4free]

Schwalbe sucks in the MTB department?!

[@FreedomOfSport]

@@pl4free The latest Racing Ralph Super Ground seem quite good and fast.

[@matthewfoote12]

Congrats on the Unbound Top 10!!