This is the type of content I want from GCN. As a technical journalist myself, I want to see Dr. Ollie doing deep dives with industry experts. He’s educated to the point where he can carry on an intelligent interview while still keeping it understandable and informative for all levels of viewers. Well done. More of this, please.
The 3 big things for me are: the drops do not do what you thought they did, tubeless over tubular and I must get some aero socks. Best vid since Inigo San Milan. These science-y, tech-y deep dives are the best of GCN. Thanks O-man!
PLEASE can we do another one about body position? It seems so crazy to discus water bottles before the question of body position which accounts for so much of the overall wind resistance! Also, a bit more about fabrics would be very informative.
Today I learned my gloves are costing me watts. Also losing watts by wearing a regular jersey instead of a skinsuit, using round bottles, etc. Good thing. I can still ride on Zwift and be virtually aero while staying comfortable.
It’s quite interesting to contemplate how using some of the things discussed might possibly help the average road rider. Specifically, lone rides vs group rides.
Super interesting talk. Thanks for that Ollie. A Q&A with questions from the audience would be super interesting. I‘d love to know if for example testing different tires is even possible for mere mortals. I‘d question that I can ride in a similar enough position over multiple runs but I have no idea how much this matters. The „don‘t have your tires wider than the rim“ rule is something really practical that everyone can adopt. More of that please.
Great interview. As somone who really suffers in the heat, I was suprised by what he said about heat not being recognized as an issue, as most riders instinctivly unzip their jerseys on long climbs. I have notced myself, on my commute (my most often used training route), that doing a max effort overdressed or in really hot weather is a few minutes slower than in the spring, slightly underdressed.
Even though I'm not particularly interested in the subject, it's always a delight to listen to an expert such as Dan, speaking so passionately about it
Two comments. 1: aero depends on speed. Same change can cause no difference at 20k/h some advantage at 30k/h and a game changer at 40! 2: the legs are interesting as they are moving much slower than the bike when coming back on the bottom, and faster than the bike when pushed in the top half circle of the motion!
An excellent and fascinating video. Though as someone who lives in tropical Singapore, I am certainly very much aware of the impact if temperature and humidity on performance
My top tips are first to buy a mirror and go side on. Then follow the Hanseatic rule of aero which is "the best way to make something faster is to get rid of it". Remove: Loose clothing Gaps in your body eg behind your head Gaps in the frame As much frontal area as you can The concept of requiring a wind tunnel is a myth. You'll get 98 percent of the way there with a mirror and a turbo, the wind tunnel is only going to be applicable for the small differences and for those riders who are going very fast and or in a velodrome
True words. However most people won't have such en easy time identifying what is better and what's not. I think this is the main reason why the bike industry changed the focus from weight to aero. Weight can be measured by anyone with a kitchen scale. The aero focus opened the world for bs marketing. This and ceramic bearings
I don’t understand why many are so obsessed about the view of their body position from the side… yes it helps to a degree but you would think that reducing your frontal area would be more critical than how you look from the side
What a wealth of knowledge Dan B is , It would have been interesting to know his thoughts the best gains for keen amateur / age group racing who do 40 k average speed not the 48 k + elite riders , ie tyre rim combination is say more important than a fancy one piece aero handle bar !?!?
Thank you Ollie for this interview. What I didnt understand was when Dan said that the internal width of the rim should be at least of the same width as the tyre… does that mean the internal width of the rim should be at least 28 mm when I use 28 mm tyre?
Thanks Ollie got the interesting video, and massive thanks to Dan for the information. Loved the 23-30mm comment, which makes us “older “ bikes owners more included in what is ok. Now what are the best affordable aero socks ?
Video idea: Take a group of average or new-ish riders and take them for a ride. Half way through give each one something different to wear or use for the rest of the ride. Aero socks, helmet, optimized wheelset or whatever. Don't tell them why or give any info. See if any notice any difference at the end of the ride.
I wish we had some numbers with the statements, things like "quite a bit", "tiny", "huge amount", etc, I'm curious to see what tests have shown. I'm aware of "well it depends" with aero, but I'm still curious to see what a test yielded even if in a lab. Really, just curious, not looking to run out and say I need a new sock to go faster.
Trainer road did this with Specialized and in general, each saving was between 3 and 8 watts, but the accumulated savings of adding this all together came to around 50 watts which is incredible.
Hope youre able to talk to Dan again i really enjoyed it. I was curious what the aero benifits of a shallow rim vs deep rim on a climb are if any? And over a mountain stage what would the time difference be?
Great interview! I didn't understand how the colour of what you're wearing works...So black or darker is better than white because it dissipates heat more efficiently, is that correct? But what about on a hot day when the sun is beating down, wouldn't white clothing reflect heat and keep the body temperature cooler, or?
I now run a 23c clincher tyre that blows put to 25c on my ri n s whi ccc h have and internal width of 23mm and external of 28c. On the back I have the 25c version that close out to 27.6mm. With tubolitos I put 80psi in the front and 90psi in the back. I just got best times changing to a more aero wheel and tyre combo.
The dream real world testing would be identical twins with near perfectly the same shape, weight, conditioning and experience. Putting them out on rides with various aero and weight tweaks, to see what really makes the difference.
Just a little tip for anyone who wants to get a hat like Ollie’s, if you can’t find one in the shops, you take a normal hat, cut the peak of the front and sew it on at the back!
Interesting stuff. Note: Having hot feet or hands, that 's actually a big deal. There's research to the fact your hands and feet especially are full of circulatory tissues that are responsible for cooling you down. EG - stick your hands or feet out from under the covers when you're hot at night, you'll cool down quickly and back to zzzzzz. Cool feet and hands on the bike likely are helping a lot to cool your whole bod.
Great video. A question for #askgcntech , we are told that deeper section wheels makes a great upgrade. Is this true of cheaper wheels or just pro level ones? Presumably cheaper ones have downsides like greater rolling resistance that offsets the aero gains - or is that complete rubbish? Also, is the aero gain linear to depth or does it drop off? Or are very deep section wheels just to unwieldy in the wind? I'm thinking 40 on the front and 56 on the rear might be a sweet spot.
Excellent points re cooling, they say wearing glasses saves 1 watt, I would argue one loses more than that especially if they're wearing glasses that covers a large prtion of their face due to facial warming.
For the last 20 years I have always ridden with a Camelbak and no bottles and have noticed how pure roadies look at me as odd. Here are my thoughts: Consider Motor GP racers have a built in hunch in their suits, I can take 2l of water/energy drink mix, tubes, tools etc. My bike is lighter and therefore more controllable. There is no additional wind drag on my down tube, not even bottle holders. How about doing some GCN science to see if I have a point or if I am just out of style.
I'm no expert... but overcoming friction only makes up part of the energy put into cycling. Even with a completely frictionless system you have to spend a lot of enegry accelerating mass and lifting mass up a height. The idea that 5% reduction of friction equates to 1 day less in a grand tour does not sound right to me. ( it would be much less)
Re cooling and no one thinking about it... Go watch the documentary on Chris Boardman's Merckx hour record attempt. His skinsuit was sprayed with alcohol before the attempt. To.... help keep him cool. That was mid 90s.
Don't forget - cycling at 15mph with a 10mph headwind is exactly the same as riding 25mph.....so any aero saving is good even though you may not be a strong rider. Another point straight arms on the drops is better than straight arms on the hoods.....I think this was confused with the aero position on the hoods.
I’m enjoying the bike so far ruclips.net/user/postUgkxMesz3KOGEmwmvyKQfLfrRSUXLFzfVHZA My only real complaints are the brakes and the pedals. I feel like a bike designed for bigger people should have much larger pedals and more heavy duty brakes. I’ve only gotten two really good rides out of it, minimal downhill action, and the brakes feel like they’re already going out. A larger person has more momentum, so I think this wasn’t thought through very well. Also, I wear size 13-14 wide shoes. My feet cramp up on these pedals that are clearly made for smaller feet. Since I’m not a pro rider (and I don’t think many are who purchase this bike) I don’t think that the straps on the pedal are necessary at all. None of this takes away from the enjoyment I get from riding, however. I’ll just head to a bike shop to improve on a few things.
Ollie didn't ask Dan about the persistent headwind that some of us suffer. Admittedly, sometimes it's only a cross/headwind. But I guess Ollie isn't old enough to have experienced this phenomenon. 🤔
With the sock isn’t because your leg is also travelling faster than you are so the air speed is much greater passing the leg? GCNs old aero expert has on his website stats on water bottle positions. Drops against hoods is difficult because of holding those positions. It’s not just cyclists that think “this is what we’ve always done” it’s people. The temp thing is obvious, do a workout inside with no fan at room temperature and you will see how it affects you. Most of us have done already. Dan was never my favourite commentator but he’s def lifting his game here. Far more personable and interesting than his usual interviews. He’s in Andorra tax dodging. 😂😂
I've been at pro rider's door and they would not take a very expensive red light therapy light for free!? They are probably afraid of the massive gains they can make ! I would take 1 for free even if i'd never use it....But i'm not a cyclist :p
Great to hear you love riding! Cycling means different things to all of us. From tech obsessed nerds like Ollie to those that just love the open road like yourself, that's the joy of cycling! 🙌
Talking 1% when it comes to a grand tour is probably a bit ingenuous. Other than the time trials the cyclists aren't running at 100% capacity for anything like the full duration of a days cycling. There's probably less than 1hr a day when the cyclists are running up against their limit. For hour records or time trials the 1% is important but grand tours is more about cycling brains and the support of the team and most importantly the ability to climb.
Ollie getting a free consultation prior to the TT season 😂
What a sneaky boy 👀
This is the type of content I want from GCN. As a technical journalist myself, I want to see Dr. Ollie doing deep dives with industry experts. He’s educated to the point where he can carry on an intelligent interview while still keeping it understandable and informative for all levels of viewers. Well done. More of this, please.
What a nice guy Dan Bigham is. I listened to him on various podcasts and thanks GCN for the video.
Glad you liked it!
Definitely the best Q and A I have seen. Well done to you both.
Glad you enjoyed it! What did you learn? 👀
I’m only halfway through this and have to comment. This is one of your best videos, thanks for hosting this interview with Dan.
cheers mate! share it if you like it. really helps us out👊
Already shared with my cycling club mates. If you have a part 2 ask him about handlebar width. 🙂
@@chrispyy606060606 Thanks for sharing! You'll be the most aero club on the roads 🙌
The 3 big things for me are: the drops do not do what you thought they did, tubeless over tubular and I must get some aero socks. Best vid since Inigo San Milan. These science-y, tech-y deep dives are the best of GCN. Thanks O-man!
Dan is so well-spoken, great interview.
PLEASE can we do another one about body position? It seems so crazy to discus water bottles before the question of body position which accounts for so much of the overall wind resistance! Also, a bit more about fabrics would be very informative.
Best interview to date! Fantastic insight, not just into aerodynamics but cooling as well. Dan really was hitting the marks. Bravo!
Thanks a lot! Glad you liked it
Today I learned my gloves are costing me watts. Also losing watts by wearing a regular jersey instead of a skinsuit, using round bottles, etc. Good thing. I can still ride on Zwift and be virtually aero while staying comfortable.
If you wear aero clothing on Zwift that makes you virtually faster though, right? 😉
Wow. Big insights! That one about the heat is interesting. 1% efficiency drop per degree is huge.
It’s quite interesting to contemplate how using some of the things discussed might possibly help the average road rider. Specifically, lone rides vs group rides.
Super interesting talk. Thanks for that Ollie. A Q&A with questions from the audience would be super interesting. I‘d love to know if for example testing different tires is even possible for mere mortals. I‘d question that I can ride in a similar enough position over multiple runs but I have no idea how much this matters. The „don‘t have your tires wider than the rim“ rule is something really practical that everyone can adopt. More of that please.
Great idea! Let's see what we can do in 2023! 👀
This is pure gold, that guy has a lot of knowledge about the subject. Thanks GCN!
We loved sitting down with Dan.. he's a fountain of aero knowledge 🙌
Great interview Ollie. Dan’s interviews are always good.
This was exceptional 👏🏾
Great interview.
As somone who really suffers in the heat, I was suprised by what he said about heat not being recognized as an issue, as most riders instinctivly unzip their jerseys on long climbs. I have notced myself, on my commute (my most often used training route), that doing a max effort overdressed or in really hot weather is a few minutes slower than in the spring, slightly underdressed.
Bet you're even quicker on the way back from work too 😉
Even though I'm not particularly interested in the subject, it's always a delight to listen to an expert such as Dan, speaking so passionately about it
YESSSSSSS
AN ABSOLUTE PHENOM FOR AERO
YAHHHHHHHHH
Haven't even started the vid but I know it'll be a ripper
Loved this, thank you GCN. Can’t believe we found a bigger aero geek than Ollie 😂
Hahah cheers!
This would also be a great long edition podcast! Interesting stuff
💡
Dan is an amazing guy! It is a pleasure to know him!
Excellent video. Dan Bigham comes across so well. Very, very impressed all round.
Great chat between "n Bigham" and "ver Bridgewood" as indicated at bottom left.
Damn Ollie, fantastic video! Priceless info and education. Who better than Dan Bingham to enlighten us. 👍
Would be interesting to see Hambini and Bigham's conversation one day...
Two comments. 1: aero depends on speed. Same change can cause no difference at 20k/h some advantage at 30k/h and a game changer at 40!
2: the legs are interesting as they are moving much slower than the bike when coming back on the bottom, and faster than the bike when pushed in the top half circle of the motion!
An excellent and fascinating video. Though as someone who lives in tropical Singapore, I am certainly very much aware of the impact if temperature and humidity on performance
Beautiful conversation! Make another one!
Thanks a lot! For something similar you could check out our 'Cornering masterclass' film on GCN+ 👉 gcn.eu/7Pp
Fascinating discussion, lots of aspects to consider. Of course, for me, aero isn’t what’s holding me back… 😁
What's your biggest barrier? 👀
@@gcntech I’m 68, 25 lbs overweight, and finally over “long COVID”. Hoping to make aero an issue inn2023! 👍👍👍
Ooooh yeeeesss Brilliant conversation 👏🏻👏🏻 answered a pile of questions on the tip of my tounge 👍🏻
Great! Glad to help
Most interesting, one of your best yet. Aero applies to us all. Thanks.
My top tips are first to buy a mirror and go side on. Then follow the Hanseatic rule of aero which is "the best way to make something faster is to get rid of it".
Remove:
Loose clothing
Gaps in your body eg behind your head
Gaps in the frame
As much frontal area as you can
The concept of requiring a wind tunnel is a myth. You'll get 98 percent of the way there with a mirror and a turbo, the wind tunnel is only going to be applicable for the small differences and for those riders who are going very fast and or in a velodrome
True words. However most people won't have such en easy time identifying what is better and what's not. I think this is the main reason why the bike industry changed the focus from weight to aero. Weight can be measured by anyone with a kitchen scale. The aero focus opened the world for bs marketing. This and ceramic bearings
I don’t understand why many are so obsessed about the view of their body position from the side… yes it helps to a degree but you would think that reducing your frontal area would be more critical than how you look from the side
Now the old “socks for Christmas” doesn’t sound so bad afterall 😂 Great vid, much love x
What a wealth of knowledge Dan B is ,
It would have been interesting to know his thoughts the best gains for keen amateur / age group racing who do 40 k average speed not the 48 k + elite riders , ie tyre rim combination is say more important than a fancy one piece aero handle bar !?!?
Great idea! Maybe we can get Dan back for a Q&A from our community 👀
Very interesting and insightful! Thanks
Our pleasure!
Thank you Ollie for this interview. What I didnt understand was when Dan said that the internal width of the rim should be at least of the same width as the tyre… does that mean the internal width of the rim should be at least 28 mm when I use 28 mm tyre?
Thanks Ollie got the interesting video, and massive thanks to Dan for the information. Loved the 23-30mm comment, which makes us “older “ bikes owners more included in what is ok.
Now what are the best affordable aero socks ?
Video idea: Take a group of average or new-ish riders and take them for a ride. Half way through give each one something different to wear or use for the rest of the ride. Aero socks, helmet, optimized wheelset or whatever. Don't tell them why or give any info. See if any notice any difference at the end of the ride.
But, maybe newish riders would quickly tire and that would distort your results.
I wish we had some numbers with the statements, things like "quite a bit", "tiny", "huge amount", etc, I'm curious to see what tests have shown. I'm aware of "well it depends" with aero, but I'm still curious to see what a test yielded even if in a lab. Really, just curious, not looking to run out and say I need a new sock to go faster.
Trainer road did this with Specialized and in general, each saving was between 3 and 8 watts, but the accumulated savings of adding this all together came to around 50 watts which is incredible.
Hope youre able to talk to Dan again i really enjoyed it.
I was curious what the aero benifits of a shallow rim vs deep rim on a climb are if any? And over a mountain stage what would the time difference be?
thanks for keeping the BACKGROUND music so low!
Would love to see another interview with hin
You need to do an aero sock shoot-out. Include some business dress socks as they appear to have the same texture as expesive race ones.
most of us didn't need this advice for getting faster, just need more time on saddle 😂
Great interview! I didn't understand how the colour of what you're wearing works...So black or darker is better than white because it dissipates heat more efficiently, is that correct? But what about on a hot day when the sun is beating down, wouldn't white clothing reflect heat and keep the body temperature cooler, or?
It's a proven fact that color-coordinated water bottles look better and go faster!
Yep! #facts
Best Q&A!
Onesie? Combined bib and jersey? Call it what it is Ollie...it's a trisuit :)
Really interesting! Unless I missed it, is there any insight on why clinchers over tubulars?
Thank you!
I have to use aero bottles to give some clearance to my legs, so I don't have to ride bowlegged like a 1850s prospector.
I now run a 23c clincher tyre that blows put to 25c on my ri n s whi ccc h have and internal width of 23mm and external of 28c. On the back I have the 25c version that close out to 27.6mm. With tubolitos I put 80psi in the front and 90psi in the back. I just got best times changing to a more aero wheel and tyre combo.
Is it possible to know what the gripper used on the saddle of the Track bike is?
What about the aerodynamic benefits of using a hub gear like the classic Sturmey-Archer three speed?
Too much internal losses on hub gears. Especially on those classic ones, Rohloff speedhub is a lot better but still not good enough.
The dream real world testing would be identical twins with near perfectly the same shape, weight, conditioning and experience. Putting them out on rides with various aero and weight tweaks, to see what really makes the difference.
So you basically mean Simon and Adam Yates then?
@@matthewgburnellhahahahhahaha😂
Just a little tip for anyone who wants to get a hat like Ollie’s, if you can’t find one in the shops, you take a normal hat, cut the peak of the front and sew it on at the back!
Tubulars has nicer ride feel then any other system
Interesting stuff. Note: Having hot feet or hands, that 's actually a big deal. There's research to the fact your hands and feet especially are full of circulatory tissues that are responsible for cooling you down. EG - stick your hands or feet out from under the covers when you're hot at night, you'll cool down quickly and back to zzzzzz. Cool feet and hands on the bike likely are helping a lot to cool your whole bod.
Is it easier to go aero on bullhorns than dropbars?
Great video. A question for #askgcntech , we are told that deeper section wheels makes a great upgrade. Is this true of cheaper wheels or just pro level ones? Presumably cheaper ones have downsides like greater rolling resistance that offsets the aero gains - or is that complete rubbish? Also, is the aero gain linear to depth or does it drop off? Or are very deep section wheels just to unwieldy in the wind? I'm thinking 40 on the front and 56 on the rear might be a sweet spot.
Top man.👍
It's true, I went out just now in just socks, no gloves, and smashed my PBs
Were you arrested for public indecency?
@@imadogsass6717 I was going to fast for them to catch me
I’ve never seen any data regarding how important being aero is while riding in a group.
Excellent points re cooling, they say wearing glasses saves 1 watt, I would argue one loses more than that especially if they're wearing glasses that covers a large prtion of their face due to facial warming.
This is fab.
Hi, you didn't ask Dan how drag effective aero helmets are on average watt %age savings.?🤓
I don't think you asked him about narrow bars or even aero bars ? Perhaps I missed you 2 talking about it ?
Philippe Gilberts example?
For the last 20 years I have always ridden with a Camelbak and no bottles and have noticed how pure roadies look at me as odd. Here are my thoughts: Consider Motor GP racers have a built in hunch in their suits, I can take 2l of water/energy drink mix, tubes, tools etc. My bike is lighter and therefore more controllable. There is no additional wind drag on my down tube, not even bottle holders. How about doing some GCN science to see if I have a point or if I am just out of style.
Good idea ... they do it in TT... UCI have some rules..
Great stuff, but the main topic remained untouched:
To shave or not to shave (the legs)?
To shave
I'm no expert... but overcoming friction only makes up part of the energy put into cycling. Even with a completely frictionless system you have to spend a lot of enegry accelerating mass and lifting mass up a height. The idea that 5% reduction of friction equates to 1 day less in a grand tour does not sound right to me. ( it would be much less)
Nice your video
Re cooling and no one thinking about it... Go watch the documentary on Chris Boardman's Merckx hour record attempt. His skinsuit was sprayed with alcohol before the attempt. To.... help keep him cool. That was mid 90s.
MORE OF THIS
Fantastic Q&A; awful Christmas tree
Agreed!
All Christmas trees are pink in Andorra 🤷🏼♂️
LOL at the "Phillipe Gilbert" chapter
Don't forget - cycling at 15mph with a 10mph headwind is exactly the same as riding 25mph.....so any aero saving is good even though you may not be a strong rider.
Another point straight arms on the drops is better than straight arms on the hoods.....I think this was confused with the aero position on the hoods.
Europe weather is always cold, try to ride in the tropical area. It is different story
Aero sock's v normal bib tights? Somebody must know!
Dan is truly a great person 👏👏👏
Is Dan Bigham Harry Potter in an alternate reality?
Fillipo has been around the block enough times? I thought he went around the track?
🙂
Morning
If socks are so important, should we be looking at shoe covers too?
In cycling the correlation between price and performance is weak.
I’m enjoying the bike so far ruclips.net/user/postUgkxMesz3KOGEmwmvyKQfLfrRSUXLFzfVHZA My only real complaints are the brakes and the pedals. I feel like a bike designed for bigger people should have much larger pedals and more heavy duty brakes. I’ve only gotten two really good rides out of it, minimal downhill action, and the brakes feel like they’re already going out. A larger person has more momentum, so I think this wasn’t thought through very well. Also, I wear size 13-14 wide shoes. My feet cramp up on these pedals that are clearly made for smaller feet. Since I’m not a pro rider (and I don’t think many are who purchase this bike) I don’t think that the straps on the pedal are necessary at all. None of this takes away from the enjoyment I get from riding, however. I’ll just head to a bike shop to improve on a few things.
Best upgrades:
Wheels…..nope
Bars……..nope
Aero helmet……nope
Funky Socks……definitely
Infinity club
The car Crash review fiesta jaguar
Dan is a great chap, with awful taste in Christmas trees.
Tree was feeling a bit naked by the looks
Ollie didn't ask Dan about the persistent headwind that some of us suffer. Admittedly, sometimes it's only a cross/headwind. But I guess Ollie isn't old enough to have experienced this phenomenon. 🤔
And it always blows the other way on the way back.
@@chrisridesbicycles Usually, even harder.
With the sock isn’t because your leg is also travelling faster than you are so the air speed is much greater passing the leg?
GCNs old aero expert has on his website stats on water bottle positions.
Drops against hoods is difficult because of holding those positions.
It’s not just cyclists that think “this is what we’ve always done” it’s people. The temp thing is obvious, do a workout inside with no fan at room temperature and you will see how it affects you. Most of us have done already.
Dan was never my favourite commentator but he’s def lifting his game here. Far more personable and interesting than his usual interviews.
He’s in Andorra tax dodging. 😂😂
Why does Ollie's hair always look like he is sitting on a Van De Graaff?
😂😂
I've been at pro rider's door and they would not take a very expensive red light therapy light for free!? They are probably afraid of the massive gains they can make ! I would take 1 for free even if i'd never use it....But i'm not a cyclist :p
I just like riding, I don’t get this race bicycle nonsense. If I were actually in a hurry I’d just take the Honda.
Great to hear you love riding! Cycling means different things to all of us. From tech obsessed nerds like Ollie to those that just love the open road like yourself, that's the joy of cycling! 🙌
“The leg aero component is important”. ? Time to rethink cleanly shaven legs and disrupt the surface layer naturally.
"Aero" is only valuable for pros, apart from that it is only money grabbing !
The biggest aero killer is you, the cyclist, change yourself first.
Then buy all the junk you want.
Talking 1% when it comes to a grand tour is probably a bit ingenuous. Other than the time trials the cyclists aren't running at 100% capacity for anything like the full duration of a days cycling. There's probably less than 1hr a day when the cyclists are running up against their limit. For hour records or time trials the 1% is important but grand tours is more about cycling brains and the support of the team and most importantly the ability to climb.
you don’t need to be riding at 100% exertion for your tyres to be running at 100%
Roll therm in glitter...I nearly shit my self laughing. Are some of the riders shit?