Aero Gains In The Wind Tunnel | Cycle Faster For Free

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  • Опубликовано: 31 дек 2024

Комментарии • 240

  • @MountainManGuy
    @MountainManGuy 5 лет назад +12

    More wind tunnel videos please! Aero wheels vs regular wheels, tire widths on the same rim compared, aero bike vs round tube bike, etc..

  • @tehArcher
    @tehArcher 5 лет назад +11

    Calculated CdA Results
    hoods (baseline) - 0.3161
    Hoods Aero - 0.2210
    Drops - 0.2377
    tops - 0.3248
    Rain jacket zipped - 0.3522
    Rain jacket half zipped - 0.3440
    Rain jacket fully unzipped -0.4005
    beard - 0.3125
    front number rectangle - 0.3398
    front number wrapped - 0.3150
    Back number fin shape - 0.3124
    (P = 0.5*rho*CdA*v^3)

  • @AR1G3
    @AR1G3 5 лет назад +9

    Probable reason for half unzipped rain cape being more aerodynamic: The air fills the vest, making it a smoother and more of a round shape . Because the air can't leave the vest there is no flow through the vest, so instead the air just flows around you. So the vest filling with air doesn't act as a parachute because the air can't leave and there is no flow.

  • @mrazzo15
    @mrazzo15 5 лет назад +28

    That number wrap around and pin up were great hacks. Was expecting the helmet design to be included there as well in relation to watts saved.

    • @treyquattro
      @treyquattro 5 лет назад +1

      I also wanted to know how much helmet design changed the numbers, also helmet vs no helmet, although that might have been seen as contributing to unsafe riding?

    • @MrBJPitt
      @MrBJPitt 5 лет назад +3

      It was "free aero hacks"....

  • @scottishjohn
    @scottishjohn 5 лет назад +1

    Liking that you got the probably the most aero rider to come and do the testing... Opie always looks aero when he is riding in general but it does go to show that if you just make small changes they can really add up and reinforces the message of how you are positioned on the bike really does make a huge difference. Hope that you guys get to go back into the tunnel and do a bit more testing... would be very interested to see what makes a bigger difference, position on the bike or changing components (deep section wheels/aero cockpit etc) Thanks chaps! Oh and please one day can we get Mr Boardman in... would love to see him on the channel especially since he does know a bit about the subject!

  • @RossTheNinja
    @RossTheNinja 5 лет назад +3

    Nice job delegating the hard work to Chris while you talk to camera. Respect.

  • @beezer946
    @beezer946 5 лет назад +2

    Chris and Ollie were great hires by the way! Good stuff GCN

  • @adqsvk
    @adqsvk 5 лет назад

    Guys, CDA is a coefficient of drag CD multiplied by frontal area A. The video suggests that it's “Coeficient Drag Aerodynamic”. Apart from that, it's another great video!

  • @ollyole4560
    @ollyole4560 5 лет назад +2

    Please do more videos with Xavier Disley, he is brilliant!

  • @sylviebouffard4896
    @sylviebouffard4896 5 лет назад +8

    Did you also test the capron? At 95% confidence interval, what was the wattage that was statistically different?

  • @Jeff-bd4gg
    @Jeff-bd4gg 5 лет назад +101

    Watching this as I ride on the trainer. As I practice the different positions my zwift avatar is not going faster.

    • @Starclimber
      @Starclimber 5 лет назад +18

      Wouldn't it be interesting if Zwift could scan your position on the bike once per second or so, and apply aero gains or penalties accordingly?

    • @JS-tb9hu
      @JS-tb9hu 5 лет назад +3

      Starclimber next level!

    • @danielandersson3539
      @danielandersson3539 4 года назад +1

      @@Starclimber Yeah, name it something like Wahoo positioner. Sensor pads on the tops, hoods and drops that can detect where your hands are and send it to Zwift. Only 300$. Maybe steering angle hits the market first.

    • @benturp3492
      @benturp3492 4 года назад +1

      Or just go out into the real world and ride your bikes!!!! 🤣

    • @ProfessorSteez
      @ProfessorSteez 2 года назад

      @@danielandersson3539 I think it’s spelled Positionr* 😉

  • @jaylumbago559
    @jaylumbago559 5 лет назад +44

    Thank you GCN, that was great content. More of that please.

    • @PrzemyslawSliwinski
      @PrzemyslawSliwinski 5 лет назад +3

      I agree! I would like to see how many watts does the everyday stuff (fenders, lamps, bags, racks, wider front/rear tires, etc.) cost.

    • @oneiilldashuffler
      @oneiilldashuffler 5 лет назад

      @@PrzemyslawSliwinski If you are asking for commuting to and from work, I wouldn't care as I think one would rarely go over 30 km/h. And if you do go over, consider it a training for a race or gran fondo as I doubt you would need that extras for the event :)

  • @anonym7122
    @anonym7122 5 лет назад +33

    oh mates you haven't stuffed your rain jacket up your front. That would have been the opportunity to check your beer belly theory.

    • @simedinson984
      @simedinson984 5 лет назад

      isnt that against the rules of the uci

    • @anonym7122
      @anonym7122 5 лет назад +3

      @@simedinson984 in their Beer Belly video they tought us that a camel bag in the front is vorbidden. But I really cant imagine that they have a general rule that vorbides to put your rain jacket up your front. Or is there? #askgcanything

    • @simedinson984
      @simedinson984 5 лет назад +1

      @@anonym7122 i thought it was for everything that filled up the jerceys front side to make you more aero

  • @alanjames670
    @alanjames670 5 лет назад

    So fascinating how the presenters keep looking at you via the camera. Watching GCN videos while high reveals many things........

  • @cocorocks88
    @cocorocks88 4 года назад +1

    Well this is useful! Doing my first local 10 mile TT tomorrow and just have a standard road bike, aero on the hoods it is! :D

  • @adambrickley1119
    @adambrickley1119 3 года назад

    Aero bottles? Flat top bars? R vs disk, etc etc.

  • @wizzy2895
    @wizzy2895 2 года назад

    I wish they thought of testing handlebar bags because I use those sometimes. Still a great and informational content though!

  • @mikewilms
    @mikewilms 5 лет назад

    Love the Video GCN. Needed to comment.
    1.The unzipped jacket was faster most likely because the air that hit the chest of the rider had an exit path around the torso and out the tail of the jacket. The closed jacket spoils the air over the front and flappy jacket actively spoils all of it. The half open jacket created a 'duct' for the air to neatly pass the rider. This works in the same way on race cars. Its not always best to divert air around the body, it will provide less drag to keep the air 'clean' through a guided duct through the body.
    2. I think the aero of the face is over looked in racing. This bearded clearly guided the air over the face and around the neck more efficiently. There are a lot of curves and crevasses on most people's faces and your head is the leading edge of your body in the profile. I wonder if an 'aero mask' that smooths the air over the face would create wattage gains in a similar fashion.

  • @davidwilson917
    @davidwilson917 5 лет назад +4

    Great work GCN! This is such good content.

  • @trbeyond
    @trbeyond 5 лет назад +3

    Can you tell your buddies over at GTN to do some similar tests on a triathlon bike?

  • @deans2239
    @deans2239 5 лет назад +2

    thanks for the great video. Something i haven't seen covered is whether higher or lower cadence makes any difference to aerodynamic drag, let's say 70rpm compared to 100 rpm.

  • @perschistence2651
    @perschistence2651 2 года назад +1

    I really wonder how a normal outfit compares here. How many watts does it take? My guess would be up to 30 watts.

  • @diegovelasquez6056
    @diegovelasquez6056 2 года назад

    Curious to know the effects of normal prescription glasses/sun glasses you'd wear daily.

  • @RossTheNinja
    @RossTheNinja 3 года назад

    Will keep wearing my buff based on this

  • @Sempoo
    @Sempoo 5 лет назад +42

    I wonder how much watts do we really gain with aerobike compared to good "normal" bike. 10 watts or more? I am also curious about TT bike.

    • @OllieBridgewood
      @OllieBridgewood 5 лет назад +12

      Sempoo depends on the speed you are travelling. With all the testing I’ve done there’s typically 20watts difference at 45kph

    • @simedinson984
      @simedinson984 5 лет назад

      20% of the drag is from the bike but usualy isnt much and 20 sounds about right

    • @taufikabidin412
      @taufikabidin412 5 лет назад +2

      The most aero bike is a rcumbent velomobile, check Saukki vid: ruclips.net/video/7wvbVa4-Ewo/видео.html, at 250 W and single rider : Road bike on hoods: , 35.3 kmh ; tribike : 37.4 kmh ; SWB bent : 39.1 kmh ; low racer swb: 42.8 kmh ; low racer SWB with tailbox: 44.6 kmh ; and velomobile is typically 49.3 kmh

    • @Sempoo
      @Sempoo 5 лет назад

      @@OllieBridgewood 45km/h is a lot... I ride at let's say 30km/h and if this function is linear, then it would be 13,4 W. Maybe that is not a lot, but quite a bit.

    • @anotherscandinavian
      @anotherscandinavian 5 лет назад +5

      @@taufikabidin412 "The most aero bike is a rcumbent velomobile" wrong channel grandpa.

  • @matthewlott5148
    @matthewlott5148 5 лет назад

    Great vid........ Just leads to the age old question....... to shave the legs or not to shave the legs (or to put some cardboard over them)

  • @ahafeezs
    @ahafeezs 5 лет назад +1

    love that shark fin theory on pinning the race number!

  • @haxhxm841
    @haxhxm841 5 лет назад

    Im seeing Aerocoach everywhere. From cade videos to your videos

  • @richaw6689
    @richaw6689 5 лет назад

    Good stuff chaps.. myth busting results there with Mr Disley. I rode with a front "Non-Aero" number at the weekend for 4.5hrs.. I had no choice but to zip-tie it across the front of the bars as per instructions from the event team.. I think it's time sportives begin using the rear mounted number like the pros. Its well Aero, looks tidy, it's smaller so saves on materials and cyclists WILL like it.. a lot! There seems no reason for the front mount at all.. no one looks at your number, other than to locate emergency contact numbers. #rearnumber .. and down off the soapbox.. 🚴🚴😀😀

  • @daveanolik8837
    @daveanolik8837 2 года назад

    Maybe an aero-science video on all the contemporary frame pack, jelly-roll, attached to aero-bar, seat-post, etc. bags currently popular? Ultra-roadie (self-supported) and XC disciplines that require both a lot of on-bike gear and higher average speeds (with rider usually on aero-bars, events like the US events Trans-America as well as the Tour Divide, etc.). I think I heard one of your folks mention that a seat-post bag provides a marginal aero gain…

  • @peterliljebladh
    @peterliljebladh 5 лет назад

    What about a backpack for committing or transportation?

  • @gordonharker4705
    @gordonharker4705 5 лет назад

    Very good video well done you 2 keep up good work.

  • @joeljstone
    @joeljstone 5 лет назад

    CdA stands for Coefficient of Drag AREA (not Aerodynamics). It's your coefficient of drag (Cd) multiplied by your frontal area.

  • @climbslc2281
    @climbslc2281 4 года назад

    Why do I love this so much?!

  • @marktatarinoff7372
    @marktatarinoff7372 5 лет назад +1

    What about the number on the side of the torso (usually track races)?

  • @TheWaxChainFanClub
    @TheWaxChainFanClub 5 лет назад +24

    Can't believe you fell for the old "merkin beard" trick, Opie.

  • @newhorizons.english
    @newhorizons.english Год назад

    We need more

  • @BFR1974
    @BFR1974 5 лет назад

    This is cool material. Good job, thank you.

  • @AandA697
    @AandA697 5 лет назад +1

    Chris pedalling Technique Shows a lot of toe down or toe dipping. There are Tons of opinions in regard to what is "better"... Maybe worth a Closer look in a Future Episode? I myself do it like Chris, but always have that Voice in my head telling me i am doing wrong... any opinions?

  • @siquq
    @siquq 4 года назад +1

    That beard was hilarious!

  • @jherexmusa9705
    @jherexmusa9705 5 лет назад

    Your personal bike is awesome

  • @BarePotato
    @BarePotato 5 лет назад +2

    I want to see numbers in few more yaw angles.

  • @errornogo
    @errornogo 5 лет назад

    CDA: Coefficient Drag Aerodynamics is wrong, it is actually CdA: Coefficient Drag Area. This comes from the drag equation F= 1/2 * ρ* Cd * A * V^2. The wind tunnel has the known values of V, ρ and the force F so a simple rearrange can give you Cd*A. Using this wind tunnel you cannot say which type of drag, skin friction or profile drag is causing the Watts saving.

  • @singingitman
    @singingitman 5 лет назад

    Could we see the results of a normal mid range bike along the differences between say 28, 33 and 40mm tyres (as these are the sizes often used by road, cyclocross and gravel riders and perhaps the upgrades people might do such as a bar change, or 20, 30, 40mm deep rims. Finally what difference do different helmets make and do sun glasses help aero dynamics?

  • @alainpfammatter8224
    @alainpfammatter8224 5 лет назад

    Very interesting video. 👍

  • @habana6595
    @habana6595 2 года назад

    Handle bar bags have to make you so mush slower than a top tube bag !

  • @JippaJ
    @JippaJ 5 лет назад

    Your best video ever.

  • @iberiksoderblom
    @iberiksoderblom 5 лет назад +1

    The aerocoach hack is awesome !
    Gonna use it everytime now.

  • @74_Green
    @74_Green 5 лет назад +67

    GCN cause a 50% rise in Beard Wax sales...

    • @Willjcbaker
      @Willjcbaker 5 лет назад +1

      A Beard Oil company was the real sponsor of this video. #MissionAccomplished

    • @TreyGruel
      @TreyGruel 5 лет назад +1

      I'm sure Óscar Pujol had already caused a boost of mustache wax sales..

  • @Fundando
    @Fundando 5 лет назад +1

    They should done more tests on beards!

  • @richardmitton5292
    @richardmitton5292 5 лет назад

    Only problem with the “aero” number wrapped round the headtube idea is that it will ruin the timing chip on some of them...

  • @petinka721
    @petinka721 5 лет назад

    Ollie is the professor and Chris the digger! Great video GCN!

  • @eurobubble7068
    @eurobubble7068 5 лет назад

    another suggestion for the next time: high drop from saddle to bar vs long reach. ive always wondered if its more aero to stretch out forward vs reach low. sagan and cancellara for example have/had moderate drop (10-11cm) but very long reach (62-63cm).

    • @Digi20
      @Digi20 5 лет назад

      i would recon its mostly up to the torso angle. so you can either have a long reach with moderate drop, or short reach with bigger drop, as long as your torso has the same angle it will almost be identical.

    • @eurobubble7068
      @eurobubble7068 5 лет назад

      the frontal area would be the same but the airflow on sides and back different, most likely better in a stretched than bulged position. thats why some of these ironman bikes have these "shark fins" on front and back.

  • @oc3144
    @oc3144 3 года назад

    What about shaving legs for aero gains??

  • @peterbroberg3081
    @peterbroberg3081 5 лет назад

    I wonder how similar the number pinned on the front of the bike is aerodynamically equivalent to any of the many cool handlebar bags for snacks and camera stuff. Seems like it would be similar, but almost 10 watts difference is a lot.

  • @the_joe_reynolds_foundation
    @the_joe_reynolds_foundation 5 лет назад

    i’d love to see how water bottles influence drag. i heard that a single bottle in the seat tub cage is faster than a single bottle on the down tube, but have zero wind tunnels to back that up.

  • @eilonshalev
    @eilonshalev 4 года назад +1

    @gcn tech, any thoughts about what is the effect of having a drafting rider behind you? intuitively, wouldn't the front rider see some efficiencies due to less drag? as in, the back rider will be facing the drag themselves and taking some of those loss wattages front the front rider, so the front rider would go actually faster if someone sits on their wheel, given same conditions of power and position?

  • @kierenkd
    @kierenkd 5 лет назад +1

    Is it normal for belly strike when riding on the drops?
    (1st road bike and working on losing the belly - about 10kg overweight).

  • @Francis14v
    @Francis14v 4 года назад

    What about bike computers, is there an optimal way to place your computer unit ? (On the stem, out in front, on the top of the handlebars, etc.)

  • @greasyfingerprints
    @greasyfingerprints 5 лет назад

    You didn't measure with the rain coat down the back of the jersey or in the pocket. Just assumed it would be more aero.

  • @ericgbarber
    @ericgbarber 5 лет назад

    What was the improvement in the Caleb Ewan position?

  • @guidospanoghe8896
    @guidospanoghe8896 5 лет назад

    What's the gain of resting your forearms next to the stem ( as if you were using an invisible tri-bar ) in comparison to the aero-hoods position? Subjectively I can maintain a high speed more easily this way during a breakaway. Very interesting stuff, keep it coming please !

  • @okletsgo9135
    @okletsgo9135 4 года назад

    The aero hoods position, is there generally a time when you want to be in this position? For instance, only in a head wind so that the wind goes over your head instead of into your chest?

  • @mattnugy
    @mattnugy 5 лет назад

    38 seconds in and I already love this video :D

  • @gefloigle
    @gefloigle 4 года назад +1

    5:30 - Whoa, hold on there professor! Rain capes keep you dry from rain?!

  • @chrispyy606060606
    @chrispyy606060606 5 лет назад

    Great video! I’d really love to see a comparison with rider on board between a non-aero frame (like a Cervelo R3-R5) versus a Cervelo S3 aero bike. Identical wheels, fit, handlebars between the two bikes. With rider on board I bet you wouldn’t see much in the way of difference.

    • @antonhelsgaun
      @antonhelsgaun 4 года назад

      Yeah the frame doesn't make that much difference

  • @SmR8008
    @SmR8008 5 лет назад

    Great video. That Bell helmet though😕

  • @ryanppax
    @ryanppax 5 лет назад

    What were those glasses Chris was wearing?

  • @Alejandrojewell18
    @Alejandrojewell18 5 лет назад

    I would be interested to know the penalty time for removing a rain cape. I.e if you are to pullover, take the rain cape off and put in your back pocket versus just unzipping it and carrying on. How long would it be before you caught up as there was a clear difference in watts. Also be useful in terms of the point in the ride. For example, If you have 5km left should I just unzip and go but if it's 15km left pull over and take it off? Any insight would appreciated.

  • @woody9382000
    @woody9382000 5 лет назад +1

    No data on the Caleb Ewan 2:28 position?

  • @RossTheNinja
    @RossTheNinja 5 лет назад +2

    Can you test wearing a buff around your neck? It's quicker to put on than a beard.

  • @joeperry9605
    @joeperry9605 5 лет назад +1

    Chris Opie has the smoothest pedal strokes of all the GCN presteners. Well except maybe Jon. But how would we know?

    • @GordonMoat
      @GordonMoat 5 лет назад +2

      Legend has it, that Jon Cannings' pedal stroke is so smooth, small animals gather by the side of the road to watch him pass by.

  • @paths2go
    @paths2go 5 лет назад

    awesome vid! Im gonna let my beard grow now

  • @AravinthTM
    @AravinthTM 5 лет назад +1

    Now can I expect beard waxes on GCN merch shop?

  • @HannesFoulds
    @HannesFoulds 5 лет назад

    HAHA, thank you for starting your new aero video in front of the fatface store, you have now become my favorite presenter. :-D
    I realize nobody will get the joke, but it is in reference to my comment on the "Can You Ride Aero Wheels In Crosswinds?" video and I at least find it hilarious. haha

  • @FallNorth
    @FallNorth Год назад

    I'm getting the mental image of the "old school" BMX number plates that were like sticking a magnicently huge plastic wind catcher on the front of the bike, bigger was better. How many 80s tight finish races might've went the other way if 2nd place had used a smaller perforated number plate? I'd love to see some 40 years later rematches to settle it, though I'd imagine the riders would also have lost some aerodynamics by now :)

  • @marianmatej5437
    @marianmatej5437 5 лет назад

    Great stuff! Next: yeti vs fully shaved man!

  • @Dayumhesgood
    @Dayumhesgood 5 лет назад

    I’m so glad we have yet another information-free video from gcn on aero with wind tunnels to point out the bleeding obvious that we have known since the dawn of bicycles (look at the guys on penny farthings getting into an aero tuck)

  • @EvidenceofaFabulousLife
    @EvidenceofaFabulousLife 5 лет назад

    Reference the beard findings, is there a case for some kind of spoiler to attach to aero helmets to fill the void between chin and shoulder. We see the clip in visor on aero helmets, could this also be applied from below to close this gap, or are there UCI regulations against this? Interesting! Ride on! Tim

  • @zurri6513
    @zurri6513 5 лет назад

    Could the half zipped cape create a venturi on the rear helping with drag?
    And the beard made me want to try a "hairy" bike, maybe having a "bike-beard" in the right places can help.

    • @percyveer2355
      @percyveer2355 5 лет назад

      @zurri dont see how the half zipped cape would give a venturi effect. i think the slight benefit may relate to the smoothing of the passing of the air. it would have been nice to see the use of smoke in the video to see how the air flow is affected.

  • @disgruntledtoons
    @disgruntledtoons 5 лет назад

    I ride with a Duck Dynasty beard. The only real problems are that it gets caught when I zip up my jersey, and if the ride recovery is in a windy place, the wind will blow it into my mouth when I try to eat.

  • @TheSamwhyte
    @TheSamwhyte 4 года назад

    Why didnt they do different kinds of helmets?

  • @stephenmoore4651
    @stephenmoore4651 5 лет назад

    I like the number pinning hacks. Not sure that a CTT timekeeper would be impressed though. Might be one for a club event only. Just need to grow a beard now :-)=>

  • @choochoo2246
    @choochoo2246 5 лет назад

    Cool insights! Thanks for the video. Question: if aero trumps all, why do mfrs continue to make non-aero carbon road bikes?

  • @treyquattro
    @treyquattro 5 лет назад

    Chris in that fake beard was hilarious! I thought Ollie should have taken one for the team here though

  • @zentrumsounds
    @zentrumsounds 5 лет назад

    Also... the CDA was 0.221 after the change to the drops. Not 0.221 'faster'!

  • @NeuesausHeszn
    @NeuesausHeszn 5 лет назад

    ... what about clothing, helmet, glasses, bottles ?

  • @404nobrakes
    @404nobrakes 5 лет назад +1

    Within 1 week, everyone is gonna go from wrinkled numbers to making fins. I’m gonna try this out

  • @RossTheNinja
    @RossTheNinja 5 лет назад

    What do people do on sportives? I'm slow enough as it is without increased drag.

  • @404nobrakes
    @404nobrakes 5 лет назад

    Update: none of my teammates were interested in the fin number because there is no evidence to suggest that it’s faster when the number is to the side and when riding with a flat back (aero position). Can we have more information on this?

    • @sudduthjonathan
      @sudduthjonathan 5 лет назад

      I was just thinking the same thing. Events/races I've done require the number(s) on the side. Was wondering with the fin technique on both sides, would I start to get airborne at higher speeds???

  • @Zzyyxx22
    @Zzyyxx22 5 лет назад +5

    Surely one should wax a beard rather than gel for maximum gains?!

  • @poormansmtb5204
    @poormansmtb5204 5 лет назад

    When I had a road bike I lived in the drop's when I get a new road bike I'll move there again

  • @jo2kids
    @jo2kids 5 лет назад

    what glasses is that?

  • @zentrumsounds
    @zentrumsounds 5 лет назад

    So just to clarify Ollie: You said here that 10 watts at 30kmh is equivalent to a 0.8 km/h speed saving and at 45kmh it is equivalent to a 0.4 kmh speed saving. You sure about that? Surely the slower the speed the smaller the equivalent speed saving not the other way around?

    • @yogatriathlete
      @yogatriathlete 5 лет назад +2

      The higher the speed, the more watts it takes to make a difference. So 10 watts at 30kmh will make a greater difference in speed savings than it will at 45kmh

  • @jaimeisreal
    @jaimeisreal 5 лет назад +2

    At 7:58. So that's how Keemstar looks on a road bike. xD

  • @Wesrl
    @Wesrl 5 лет назад

    When I was getting my bike fitted they told me I would be better off being on the hoods in an aero position then on the drops in one since im not as flexible

  • @bradcomis1066
    @bradcomis1066 5 лет назад

    Does Boardman cycles own this wind tunnel?

    • @AngadSingh108
      @AngadSingh108 5 лет назад

      it's in the Boardman Performance Centre at The Valley in Evesham...

  • @8N_TT
    @8N_TT 5 лет назад +2

    My bike has ultegra 6600 levers, sometimes I hold on to the cables to get aero, but it's kinda risky.

    • @95Nikoss
      @95Nikoss 5 лет назад

      Hahaha it is a bit crazy yes
      Beautiful groupset btw

  • @Aditya-fv9xv
    @Aditya-fv9xv 5 лет назад

    Ollie's fresh haircut gets a "super nice" *ring ring ring ring ring*

  • @raybarber9837
    @raybarber9837 Год назад

    I've noticed that whilst Si's face always looks as smooth as a baby'bum, Alex only had a passing relationship with a razor. How many watts does that cost him?