Tyre Pressures: Tech Talk with Simon Crafar

[@thirdworldTrini]

Love Simon... and when I say Simon I mean Crafer 🙌

[@kashishsubhani]

I see what you did there 😂

[@christianhardwick6530]

Dylan Gray is the best !

[@anel3317]

@Abhirup Nath We are all sure you would do much better. You are probably champion at your work and hobby too and everyone loves you. Simon - thanks for another great knowledge share.

[@zorancendic4001]

Thank you Simon,good explained👏👏👏👍🏁

[@PattiTalks]

Two intact bikes of Alex Marquez in the pitbox? That is unique, this video has to have been recorded on Thursday :D.

[@marks.17]

Cruel but true.

[@PROTEUS_SEER-OF-EONS]

I study MotoGP to apply the principles to my spirited canyon rides on my Dyna. Many have saved me, and improved safety.

[@borscheproductions3077]

I demand more Simon!!!

[@atostesjr]

Another great video Simon, thank you. A sugestion for another video about tires: I would like to know about the differences in structure (carcass rigidity) between racing tires, supersport tires and sport tires. For example: Pirelli supercorsa SC, supercorsa SP and Diablo Rosso IV Corsa. Tracks don't have potholes like the streets of many countries, but forces from braking acceleration and corner are much bigger. So what demands a stiffer carcass: high forces or big potholes? If someone can comment it would nice!

[@lukabijelic]

Man I love MotoGP 😉🤙

[@ปฏิภาญบัวเผื่อน]

Man I love MotoGP

[@backtothefuture4268]

I miss racing during the early 2000s, at that time with Bridgestone tires we could see interesting races. From the start to the end of the race, with bridgestone rider tires, there is no need to do tire management

[@rizkisyatiaahmad3119]

same feeling with u bro

[@aakash4351]

Yeah top riders were much closer. Now a days one of them just flies away and the fight is for 2nd and 3rd position.

[@backtothefuture4268]

@aakash singh Yes you absolutely right, no doubt The philosophy of michelin tires is different from the bridgestone tires, the michelin tires have a philosophy that the rear tires have a major role in determining the speed of the bike, while the front tires are limited to withstand the stability of the bike during braking, this is what causes many low-side riders and loses grip. This is not suitable for riders who have an aggressive riding style, Bridgestone tires have a balanced grip, with Bridgestone tires being suitable for all riding styles,

[@backtothefuture4268]

@Abhirup Nath th1s 1s p4rt ofd02n4 pl4n t0 k1ck V4le,stoner In various ways they want to kick Valentino and Stoner, and keep their pets returns Marc and the Spanish riders edwards was said:Complete joke!!!! No wonder Casey [Stoner] has lost his passion when u see all cards stacked against ya....ridiculous!!' quoted from,crash

[@HighLiner15]

I'm curious 🤔 Why don't they use Nitrogen in their tires like other forms of motorsport?? Or run pressure bleeders to maintain a max pressure??

[@GiorgiLaluashvili]

probably regulations

[@HighLiner15]

@@GiorgiLaluashvili most likely your correct. I wasn't sure if they were allowed or not

[@mikaelgaiason688]

Nitrogen is a gimmick sold to people by tire shops. There's no way to pull a vacuum on the tire to remove all the air in the first place, and even if there was it would be pointless. Regular atmospheric air is already mostly nitrogen, adding a percent or two won't have any difference

[@kiwialfa2083]

Air is 78% Nitrogen. What causes most of the variation in air pressure with heat is water vapour in ambient/moist air, not the 21% oxygen and 1% trace gases. So the key is the absence of water. Dry air has a know reliable pressure increase rate, as does 'dry' nitrogen. In the real world the advantage of nitrogen over dry air is marginal.

[@HighLiner15]

@@mikaelgaiason688 F1, NHRA, NASCAR, World of Outlaws sprint car teams would disagree.....

[@geetarthneo]

As usual, great video. This video not only helps us understand MotoGP but also our own bikes. And also, I thought MotoGP uses nitrogen in its tyres.

[@Chris675R]

Air already contains 77% nitrogen, so you would only replace the 23% oxygen, which is not that much of a difference. The difference between dried air and 100% nitrogen is way bigger in terms of consistency and predictability that's why they use that in motorsports.

[@bermainceria2901]

Indonesia ❤️

[@mandalaputrapratama975]

Motorgp terbaik 👍👍

[@jish8080]

Beautiful pitline,beauty of motogp bike since lcR👍 garages.

[@timjamesvella]

I thought it was the other way, lower pressure allows the rubber to flex more, creating more temperature. Higher pressure, reduces the flex hence lower temp?

[@kiwialfa2083]

On the road, on treaded street tires it does. I'm willing to accept slicks at temperature being constantly pushed to edge of adhesion may react differently. Especial when a former GP500 Grand Prix winner says so.

[@barringtonsharpe2402]

I took away that tires can heat up for various reasons, carcass flex, ambient air heat/convection from brakes , exhaust and road surface etc. Simon explained one aspect in which a narrow contact patch gets overworked then too hot etc. This is a very dynamic environment in which there are many variables hence the difficulty in getting pressures right. A lot of experimentation is needed on a given race weekend starting with baseline data and past experience . As an example once in a fellow coach couldn’t keep up with a student while accelerating out of a corner on the same year make model bike . Our deputy chief riding coach suggested increasing rear tire pressure by 5 psi this worked and stopped the rear spinning. We figured out the increased tire pressure caused the tire to press harder onto road surface. (Similar to using narrow tires in show vs wider tires). Hope this makes sense

[@yangwang6952]

FIM is monitoring tire pressure during the race week and found many time the lower pressures against minimum pressures of in many cases Ducatti. Why FIM didn't eliminate the bike with irregular tire pressures from the result.I don't want to watch the race in which Michelin decides the result controlling the tire pressure.

[@shaheerdanish55]

0:11 i heard this weeks tiktok 😂

[@wertawonka]

So the tyre technicians can control the races!!!!! I fucking knew it was fixed

[@Nomads_Rowing]

No pressure there then on the tyre technicians Simon😎

[@jaikanths875]

Anyone wondered when he was going to do the TikTok video?

[@kecxdroid1869]

Tasas que me duermo, aquí son las 4:41 a.m. jajajajaja

[@rizkiirawan3841]

HRC 73 A Marquez

[@timsalabimbombassa]

I used to think that low pressure gave higher temperature, because the rubber moves around more... Guess I was wrong all my racing years

[@lachlancrutchfield1916]

That's what I thought too?

[@yamatoSVK]

and you were right ... the lower the pressure, the more the tire carcass flexes and generates more heat in the whole tire, the only case where the low pressure would cause temperature drop is on cold roads where the asphalt cools the tire down faster than it can generate heat, too much pressure will cause local heating and you will get "cold tear", where the tire heats on the surface only on small patch and tears itself off from the base which is still cold (hence the name cold tear), at least that is how it to my knowledge and basic physics understanding works, I'm not an expert, but I have a feeling when the experts were explaining it to him, he misunderstood something ...

[@lachlancrutchfield1916]

@@yamatoSVK that is what I thought, maybe in MotoGP the track temperature is more of a consideration than flexion? But the way Simon explained it sounded like maybe not... I don't know..

[@PavelGarashchenko]

You were right of course. Simon - not, unless he meant the "local heating". The tire heats more with lower pressure. And if the tire heats too much - then technicians raise the pressure a bit to reduce the heating (meaning that with higher pressure the tire heats less).

[@kiwialfa2083]

kzbin.info/www/bejne/bpjXYWqers-if6M Watch from 5.27. information is from Michelin

[@adityadesai5135]

Am I the only one who heard "this week's tik tok"

[@jordanfranklin189]

Not the topic is thought would be my favorite video keep em coming boys

[@piotrkobielus6156]

MotoGP

[@Al-of3zp]

3:11 busted!

[@piyushwarole2716]

Where is friday gp of todays

[@Longboardmaestro]

Didn't know we need low tyre pressure when doing track days

[@TheInfantry98]

Yeah it’s common knowledge

[@Longboardmaestro]

@@TheInfantry98 well, we learn something new everyday!

[@lonpfrb]

@@Longboardmaestro Check out the Dunlop NTEC design that allows a road pressure setting and a track setting for the optimal running pressure and temperature. That's ideal for occasional track use, so ride to the track, go fast, and ride home..

[@mikaelgaiason688]

You're paying the wrong trackday organizers. We always have a sheet on the side of the trailer right next to where the time-sheets get hung, with suggested starting temps for all the common tires based on expected track temps. Everybody gets told about it during the riders meeting

[@sajeev7469]

Wow!!

[@robertopereira11]

Aquí son las 12:08

[@636theofthebeast8]

Tech talk > Tik Tok

[@lenyora07]

That's what Yamaha got wrong in Aragon and Fabio was struggling

[@hhxlegacy]

Thumbs up if you heard him say "this week's tiktok".

[@nathanmiller5209]

Thanks Simon, love your explanations, hope you can lose the mask soon.

[@greglockyer4335]

1 bar is 14.7 LBS at sea level. Altitude decreases the pressure. So at a 1000 feet above sea level 1 bar depending on temperature could be 14.4 LBS. Hehehe can get a little technical people. Just a point of view from a farm worker 👍🤔

[@nolimits300]

Farm worker?! (😂) C'mon what are you hiding?! 👍

[@brentfrank7012]

You don’t need a mask with no one around you and filming a video. Your viewers need to hear what your saying. But great content, thank you.

[@mikaelgaiason688]

He spoke clearly. I understood every word he said, did you not? Either way, if it's a problem there's a caption button... He's being a responsible adult and setting a good example, nothing wrong with that

[@claudemaggard7162]

They use nitrogen not compressed air

[@qhairunnissaaulia8451]

🔥🔥🔥

[@haspankid5173]

Akhirnya pembalap ini disorot lagi meskipun cuma motornya

[@edr_tv]

Mugello💪

[@erm1tal93]

Valentino rossi!!!!

[@jaycon3460]

Appreciate Crafars tech talk but sure sounds like it's all been overcomplicated.

[@dipling.pitzler7650]

Because of the life long practice and riding of Motorbikes a lot of GP pilots suffer from O - shaped legs like Simon Crafar does, clearly visible in this video.

[@rameshad8572]

Marc

[@dey-oe8sb]

The doctor 46

[@jadesmith6823]

One can have a K in power however, if balance and play is lost then why bother 🤔😏👍

[@surendrareddy8250]

09

[@thomasreyes2857]

When he said dry air I think he was trying to say nitrogen 😬🤔🥴

[@kiwialfa2083]

kzbin.info/www/bejne/bpjXYWqers-if6M Watch from 5.27. information is from Michelin

[@aliefsuryo]

Ayy

[@mandalaputrapratama975]

😘😘

[@三號白猫]

日本語字幕を是非ｗッ‼(T_T)ﾉｼ

[@siddharthmane5642]

Explanation is too confused OK any way sir I try to underground

[@higaditos]

He really likes TikTok

[@umerkhan4818]

Who heard tik tok instead of tech talk???

[@ametti000]

All we learnt was that the pressure goes up when the tyre gets hot. The tyre is the most important thing on the bike and this is the best you can do. Not a great tech talk.

[@kiwialfa2083]

May be watch this one as well? kzbin.info/www/bejne/bpjXYWqers-if6M

[@hardyanpajero69]

👍😎🍺🍩🏍️🏍️

[@АлексейГуринович-щ4ж]

Why are you wearing a mask next to no one?

[@mikaelgaiason688]

Why are you so offended by a mask?

[@borushiki06]

First

[@joelramdinmawia6616]

sir your reviews are accurate but the mask is muffling your voice😓

[@ash170568]

Take the damn mask off, you are standing by yourself.

[@Gramercy_Stiffs]

Yeah and holding the camera too right.

[@ash170568]

@@Gramercy_Stiffs the camera man will be more than 2 meters away from him. It is time to start ditching the mask when the situation allows.

[@mikaelgaiason688]

Why are you so offended by a mask?

[@ash170568]

@@mikaelgaiason688 I am not offended by the mask but the guy is far enough away from anybody else and I want to see his expressions as he's talking. The masks achieve nothing, so when speaking to cameras or when being interviewed remove the mask so we can see the person properly.

[@mikaelgaiason688]

@@ash170568 It's a waste of time to constantly take it off and put it on. Easier to just leave it on. Eyes are the most expressive part of the face. If he was wearing shades I'd understand, but he's not. Taking the mask off doesn't achieve anything but appease people who let their politics dictate their lives

[@yusryusril3930]

Rossi winers and podium 🎉

[@PhilbyFavourites]

Squash the tire under braking….. He’s obviously not seen me sauntering along the back roads of Southern England. Those squashing their tyres into the tarmac usually end up squashing their bodies into a tree on the A272. But honestly I watched this all the way through and it was dull to the Nth degree. I don’t know how differently our presenter could have done it. But in honest critique - he was boring and although knowledgeable he just isn’t making the grade.

[@lonpfrb]

Racers are doing research and development at the extremes so that the product is tested, and you can saunter within a large safety margin. The front race tyre is likely about 30psi as against 36psi for road use. So much of the stability comes from the tyre carcass and the rest from the air pressure. Typically the front has to support 200kg bike plus 80kg rider so that's a lot through one contact patch 120/70R17. Even moderate riding will be squashing the front, though you can't see that from on the bike. The front wear width will give a fair Idea that you can see when stationary. Ride safe..

[@PhilbyFavourites]

@@lonpfrb Don’t worry I realise the time effort and research put into tyres and their technology. I guess my sauntering has been set from an early age: I chose the Avon Roadrunner over the Dunlop TT100 back in ‘76 for my then very new Kawasaki KH250. Over the years that’s morphed into a 1250GS and that Telelever disguises the fork dive (ant tyre squashing…) very effectively.

[@kiwialfa2083]

I you don't like it, don't watch it. Problem solved.