I know you are probably not going to read this, but I just wanted to say thank you! Thank you for all your videos. I have learned so much of your videos. When i started watching them (1year ago) I didn't know anything about cars. But now I have watched every single video and I feel like I will never lose interest. I'm 16 year old Bulgarian (who cares ?) and my dream is to study Mechanical Engineering in the US when I finish high school. You have no idea how much you have inspired me and helped me in my life. PLEASE carry on doing what you do. Once again THANK YOU!
@@dhxl Wow I completely forgot about this comment, it was so long ago haha. I am 21 now, actually studying logistics engineering in the Netherlands. Life is good so far and future looks bright. Thanks for asking! Best wishes!
This is a really, really good video. I'm studying engineering and am familiar with the concepts, but having it distilled so nicely was still very enlightening. Normally most educational videos can spend time explaining the ideas behind each variable, with flashy but meaningless demonstrations, but without providing specifics in terms of which direction of impact each variable has, trade-offs, non-linearity, how they interact etc. Your channel and old school 1940s documentaries are the only ones that get this right when explaining technical content. Thanks for making it!
Nice to learn that we can have the cake and eat it too. I always thought tires was a choice between high durability, low-rolling resistance but with a hard compound with low grip or vice versa. Nice to know we aren't too far off with this technology to be applicable to cars with both a performance & economical faces.
+Trades46 It still is, but less than it used to be. With silica we can achieve higher grip with the same rolling resistance than before, or lower rolling resistance with the same grip than before. Or somewhere between the two. As silica technologie advance, we can make the difference in response at low and high frequency increase, thus increasing the grip and / or rolling resistance even further ;)
Excellent video, extremely well explained. It's good for drivers to understand the basics of what a tyre actually does in contact with the road and how that affects the vehicle. Considering that the tyres are the only bit of the car that actually touches the road, they're very often an overlooked aspect. Great job once again!
I just put them p zeros on my Hyundai Accent, they were expensive but so so worth it now my car doesn't slide about as I hoon it while racing ferraris and bugattis
+Hyundai Accent Fan Club My mustang came with P zero summer tires and honestly I'm not a huge fan but then again it could be the fact the rims are 20 inches, I'm debating pilot super sports anyone here think they would be better?
This is a great explanation! It completely changes the way I understand rolling resistance. I used to think it was only linked the tire tread pattern and surface contact area.
Hey! Cool! I learned about polymers storing mechanical energy as thermal energy on an old JoergSprave video (he was talking about why slingshots work poorly in cold temperatures relative to warmer temperatures) - it's cool to see the tie in between two very different usages of the same mechanic.
That's sooo cool. These are the sort of eco developments that we need, those which improve fuel efficiency but without having to trade off something else for it. These tyres might be more expensive at first, but dependent on the amount of fuel they save they may well prove an economical choice immediately. There should be no reason that this technology isn't on all cars, with the potential savings in emissions being huge. Great stuff.
+Tamás Madarász yes but because of the weight of the cart it presses onto the rail creating the grip, thats why low weight high performance cars need wings to press it onto the road to create grip,
+GraveUypo Actualy my school won at this competition several times and the tires are about the same rolling resistance as Steel on Steel. But they are very fragil, a stone and they are broken. They are very very thin and have high pressure (4-7 times the pressure of normal road tires)
That was a pretty cool video. The silica compound reminds me of when you mix cornstarch and water and it's like liquid but gets hard when you apply pressure to it.
I would be interested in how that relates to off the shelf products. I have always thought there was a linear relation to resistance vs. grip. but this video was very informative to show both can happen. A series of videos on tires would be very interesting. Good video thanks.
Awesome video! I've always wondered about the magic behind LRR tires ever since I bought a set on a whim a few years ago. Their contribution to overall efficiency is minimal compared to the other resistive forces, but working as part of a system designed to be efficient, they definitely make a difference! Talk to any tech-savvy long-term Prius owner and they'll tell you all about their adventures with different wheels and tires. :)
A topic suggestion: I am interested in the science of "hard break-in" vs "normal break-in" of new vehicles. What's your take on it? I am sure it would make for a great topic for another video
Interesting EE. I swapped out the stock Michelin tires that came with my FR-S for Michelin All Weather Super Sport tires. The mileage is slightly less than the stock Michelins, which were optimized for high mileage, but it is a good trade off for me because I like the handling of the Super Sports much better. And after all handling is what the FR-S is all about.
Awesome!!!!!! everything explained easy and quick. I was wondering if you can make a video to explain engine load ? There's many videos around where you plug in an obd dongle to display engine load in percentage and this info can be used to improve fuel efficiency. Great videos!!!!!!!!!!!!!
I learned about this in a lecture. The different energy loss factor of rubber in different frequency ranges is explained by the Williams-Landel-Ferry diagram - rubber with silica additive has higher energy loss factor in low temperature range and lower energy loss factore in high temperature range. I just can't figure out why braking (high frequency) corresponds low temperature.
Thanks. I got it now why Firestone Firehawk Sport 01 (Bridgestone Potenza Adrenalin RE002 reincarnation) which has high rolling resistanse the same as RE002 has very high grip, but less fuel efficiency.
Very interesting!!! one think I don't know why happens is: why does a tire lose its grip while wearing down? doesn't the tires have the same compound throu all the profile? You can notice that more dramaticly in motorsports...
+GogogoFollowMe That's the goal. This is something Michelin is currently trying to demonstrate in Formula E, as they don't have tire swaps so the same set of tires have to last through practice, qualifying, and the race. I've spoken with a few team engineers and they say the degradation is very low.
+GogogoFollowMe I guess it would depend.... I drive a lot for work so I have two examples: I have a sports car with very soft tires. At first I thought that they wouldn't last, but They lasted over 70,000Kms with a double wishbone front setup and multilink Rear RWD. ( Can't rotate due to the different front to rear sizes ) I also have a small hatch back with tires that were about the same 140 treadwear and they only lasted 40,000kms with a McPherson front setup and torsion rear... FWD and 1/2 the HP. ( Rotated every 15,000km) Still not that bad. I also check and adjust the tire pressures weekly, so they are never low or high. I assume that the life depends on too many factors, including the setup of the car, how you drive, types of road etc....
+GogogoFollowMe Well if you look at the 2010 Formula 1 Bridgestones, where the disbenefits of the tire degradation is less than the benefits of weight loss from fuel throughout the race (net benefit from the two factors), if my memory serves Sergio Perez ran 80% of the race on a set of Options in Valencia. Correct me if i'm wrong, but i do remember him racing a very long stint on one set of tyres. That's one mighty compound Bridgestone got there.
I think it really depends most on how you drive. I don't think that sort tires would wear out fast if people weren't putting excessive stress on them. If you increase the stress, you increase the wear.
There is no practical incentive to commercialize a high-grip tire with minimal wear. They want to make money. Their commercial formulas would be centered on some exec's cost-benefit analysis.
That's awesome! Any word on when this will become available to the public? I'd imagine it'll be pretty expensive for a bit until they're able to get costs down, though.
The tech has actually been around since 1992 when Michelin first invented it, but they've been improving it ever since, and it's transformed the industry as everyone now uses silica compounds.
+Engineering Explained How does the wear of the compound compare to earlier versions of radial tires? If it has high grip I would imagine it would wear quickly, similarly to a performance oriented tire but with low roll resistance I would imagine it may negate this effect of wear.
Michelin is currently selling tires to the public with high levels of silica. The Michelin Premier A/S and the Michelin Pilot Sport A/S 3 are two examples. Go get them! I have the A/S 3 on my car, awesome tires!
From what I remember from school, "Hysteresis is the dependence of the state of a system on its history." How does this work with your definition of hysteresis?
Michelin also makes special tires with low rolling resistance for Solar Car competitions (American Solar Challenge and Formula Sun Grand Prix). I'm on the University of Kentucky Solar Car Team and trying to get some for us, but they're definitely hard to get...
Interesting video, I didn't know about the importance of silica on the energy losses prior to this. However his demonstration with the "silly putty" was innacurate, because it had higher losses at low speeds and less losses at high speed (opposite to what you explained in your graph).
+Richard Andersson Haha, everyone keeps mentioning this - at 4:53 he mentions that tires behave exactly the opposite. The demonstration shows that you can manipulate the behavior of a compound depending on the speed of deformation (frequency). Tires will have high energy losses at high frequencies (where as this 'putty' he's using does not).
Engineering Explained Sorry, I completely missed that. I would however be very interested in knowing why silica makes rubber behave the opposite. All normal plastics are viscoelastic (opposite to what you want in tires), such as rubber without silica, plastic bags or even silicone based compounds such as "silly putty".
Based Frenchies. I really wish I could have had some high-performance summer Michelin's for my car, but they only had standard touring tires. They have top-teir all-seasons, but I was dead-set on summer tires.
How do the Shell Eco-Marathon tires achieve one-fourth the rolling resistance of steel wheels on steel rails? Perhaps the rubber compound deforms more than steel, but loses a lot less energy to hysteresis per unit volume deformation. It kind of checks out when you consider how low of a height a steel ball rebounds to when dropped compared to a rubber ball.
This was awesome! I wonder how significant the difference in price is... If a tire with this technology is much more expensive, it completely undoes the benefits of it lasting longer.
So, non-Newtonian rubber? Also us older guys used to work on a 4 PSI difference between cold and hot. So if your tyres are inflated to 34 PSI when cold, they should reach 38 PSI when hot, and no more. If they increase more than 4 PSI when hot, your cold pressure is too low and needs to be increased. If they go up less than 4 PSI when hot , your tyres were over inflated when cold and should a lower pressure when cold. Car manufacturers usually go for comfort which is too low when cold. Not sure if it applies nowadays. Replies welcome.
Please answer: What are the realistic and verified rolling resistance coefficients? or at least approximations. Train rolling resistance varies too much to get specific coefficients from the comparison. Are we talking about less than 0.001?
Just to set things straight, the silly putty is "exactly the opposite" of what the silica tire does. And, the low frequency is the tire ROTATION at driving speeds; the high frequency is the IMPACT with the road. tldr, low rolling resistance, high resistance at micro scale contact with the road.
So it's a non-thixotropic dilatant fluid? How does it keep its shape when it's in the tire? I'm assuming there are solid compounds in the tire material matrix that act as a clathrate with this new STF material and the two subset phase types (plastic solid/fluid) combined act as a Bingham plastic? Great video, thank you!
sorry for my English, but I wanna ask: As we were explained, if we want low rolling resistance we need a tire, that is hard at low frequency deformation, so, it needs to be hard when you deform it slowly. From another angle, we need soft, elastic rubber at high frequency deformation, if we want to have some grip. It means that tire need to be soft, when it deforms quickly. BUT, what we saw on demonstration whit the sample of rubber is totally otherwise! The sample is hard, when deformation is fast and soft when it's slow. Won't the tire be high rolling resistance and with no grip, if it's made of this rubber we were shown??
in the video he said that silica are highly deformed with slow speed and dosnt deform or less deformed with high speed and he also said that in the car it's opposite so how we use it in the car
I wonder if it is the rails deforming. At every track I've been around, you can see the ties moving and if the bearing structure is moving, the steel on top of it has to be moving as well.
Fascinating. I think I've missed or didn't grasp the concept though, regarding how silica's high deformation at low speed and less deformation at high speed (instead, breaking) helps maintain grip at high speed (frequency) while providing low rolling resistance at low speed (frequency). Wouldn't it cause the tire to deform *more* at low speed and *less* at high speed? Is that accurate? Or is it that it deforms more while stopped or at low speed, allowing for traction off the line, but then quickly firms up and reduces rolling resistance once the tire is moving? So while it will perform better from a stop, it likely won't handle cornering or high performance as well as a sport-oriented tire (such as their Pilot Super Sport tires).
I spotted the exact same logic error. You want the tire to not deform when done slowly and deform when done quickly. And the exact opposite was demonstrated.
The guy said the demonstration of pulling apart the silica compound putty shows the exact opposite effect to tyres with silica compound?? I'm confused - pulling apart the putty quickly (ie high frequency) leads to it breaking into two, but don't you want it to deform slowly at high frequencies to simulate grip?
+Simon Zhao Well, low resistance tires grip will probably improve when this new technology comes to the market. But, I agree, for now it's better to go with a regular tire, not a fuel saving one. I can recommend Conti Premium Contact 5. Excellent wet grip, almost as good as when it's dry. Crazy really.
Get a tunable ecu to adjust a/f ratio, new MAF, bigger injectors(probably) front or sidemount intercooler for turbo, oil cooler, waste gate/turbo timer, blow off valve, upstream 02 sensor(s) and possibly bigger exhaust
Interesting video. One question: shouldn't rolling resistance be measured as a dimensionless number, rather than kilograms / ton? (A ratio of masses, doesn't make much sense at all, except that it's a ratio.)
Hi, I am Abinash. This , video was really cool, but can you compare between these Michelin tyres and bridgestone ecopia(ologic) that was used in World Solar Challenge Australia 2015
collaboration video done right, we learnt something, Michelin got some exposure 👍
Thumbs up. :)
I know you are probably not going to read this, but I just wanted to say thank you! Thank you for all your videos. I have learned so much of your videos. When i started watching them (1year ago) I didn't know anything about cars. But now I have watched every single video and I feel like I will never lose interest. I'm 16 year old Bulgarian (who cares ?) and my dream is to study Mechanical Engineering in the US when I finish high school.
You have no idea how much you have inspired me and helped me in my life. PLEASE carry on doing what you do. Once again THANK YOU!
So, how are you doing today? Are you still interested in mechanical engineering? Which university have you chosen?
@@dhxl Wow I completely forgot about this comment, it was so long ago haha. I am 21 now, actually studying logistics engineering in the Netherlands. Life is good so far and future looks bright. Thanks for asking! Best wishes!
@@gberbenkov 👍
Its amazing how much is happening in the tyre industry - we really need to appreciate this seemingly simple rubber ring more
+Martin Fisker Like Chris Harris does.
I like how you explain things on a different way.
My English is not perfect, but I near all understand :)
Greetings from Europe!
+MrNordlandfahrer Like mathematics, engineering is a universal language. :D
This is a really, really good video. I'm studying engineering and am familiar with the concepts, but having it distilled so nicely was still very enlightening. Normally most educational videos can spend time explaining the ideas behind each variable, with flashy but meaningless demonstrations, but without providing specifics in terms of which direction of impact each variable has, trade-offs, non-linearity, how they interact etc. Your channel and old school 1940s documentaries are the only ones that get this right when explaining technical content.
Thanks for making it!
grip > efficiency .. i rather drive with grippy tires and have a worse fuel mileage.
But having both would not harm hihi :D
Great video
Nice to learn that we can have the cake and eat it too. I always thought tires was a choice between high durability, low-rolling resistance but with a hard compound with low grip or vice versa. Nice to know we aren't too far off with this technology to be applicable to cars with both a performance & economical faces.
+Trades46 It still is, but less than it used to be.
With silica we can achieve higher grip with the same rolling resistance than before, or lower rolling resistance with the same grip than before. Or somewhere between the two.
As silica technologie advance, we can make the difference in response at low and high frequency increase, thus increasing the grip and / or rolling resistance even further ;)
+Joe Blogs I don't know were you get that from. All road tires use silica and modern road tire performs better on wet roads.
seems like every company is discovering the magic of silly putty right now :^))
Excellent video, extremely well explained. It's good for drivers to understand the basics of what a tyre actually does in contact with the road and how that affects the vehicle. Considering that the tyres are the only bit of the car that actually touches the road, they're very often an overlooked aspect.
Great job once again!
It was nice meeting you there! Keep up the good work
Man, this was a perfect video, totally understood what was being explained, and giggled as I did; Thanks Chief !
Keep on trucking ! (from France)
I just put them p zeros on my Hyundai Accent, they were expensive but so so worth it now my car doesn't slide about as I hoon it while racing ferraris and bugattis
+Hyundai Accent Fan Club Not really a fair comparison, the Bugatti never stood a chance against your Accent.
+Engineering Explained fair point fam
+Engineering Explained So, that new compound is like oobleck?
+GrimFaceHunter At about 4:50 he says it's the opposite on the tires. So, backwards oobleck.
+Hyundai Accent Fan Club My mustang came with P zero summer tires and honestly I'm not a huge fan but then again it could be the fact the rims are 20 inches, I'm debating pilot super sports anyone here think they would be better?
The Michelin engineer did a awesome job. Super video. Thank you +Engineering Explained
This is a great explanation! It completely changes the way I understand rolling resistance. I used to think it was only linked the tire tread pattern and surface contact area.
+TheReacTT Happy to hear it; I learned quite a bit myself, as I was never sure what the relationship between grip and rolling resistance was.
Learned something new. Interesting is also that silica waxes are used for asphalt do extend the plasticization range.
Awesome video. Thank you for the clear explaination!
+mrawesomelemons Glad you enjoyed it, thanks for watching!
+Engineering Explained so if i'm correct these compounds are essentially non newtonian things.
+Engineering Explained
a question you may not answer >>>
explain fuel vapor !
You, sir, are my new favorite UA-cam channel! German engineering greetings!
+oTK89o happy to hear it, thanks for watching! :)
Who tf dislikes a video about car tires?
They think car pollution is the cause of all their problems, or he doesn't wrench enough and expects people to think instead? Lol
ha ha ha...
Hey! Cool! I learned about polymers storing mechanical energy as thermal energy on an old JoergSprave video (he was talking about why slingshots work poorly in cold temperatures relative to warmer temperatures) - it's cool to see the tie in between two very different usages of the same mechanic.
I got distracted by the kids and had to watch it again
The kids were distracted as well, all good!
That's sooo cool. These are the sort of eco developments that we need, those which improve fuel efficiency but without having to trade off something else for it. These tyres might be more expensive at first, but dependent on the amount of fuel they save they may well prove an economical choice immediately. There should be no reason that this technology isn't on all cars, with the potential savings in emissions being huge. Great stuff.
This was extremely cool and informative. I absolutely felt like I learnt something! Thanks for the video!
The rolling resistance of those tires on asphalt is 1/4 that of steel wheels on a steel track? Whoa.
+Tamás Madarász yes but because of the weight of the cart it presses onto the rail creating the grip, thats why low weight high performance cars need wings to press it onto the road to create grip,
+Tamás Madarász yeah, i think he meant four times not a fourth
+GraveUypo I think so, cuz that just sounds wrong
+GraveUypo Actualy my school won at this competition several times and the tires are about the same rolling resistance as Steel on Steel. But they are very fragil, a stone and they are broken.
They are very very thin and have high pressure (4-7 times the pressure of normal road tires)
wouldn't this make trains obsolete?
you should revisit this topic in in greater detail. I really enjoyed it.
It's funny that the visual aid was silly putty because silly putty was originally invented to try and make synthetic rubber.
Would you say that the choice of the visual aid was silly?
That was a pretty cool video. The silica compound reminds me of when you mix cornstarch and water and it's like liquid but gets hard when you apply pressure to it.
You mean oobleck?
+Forged Garage look for non neutonian fluids
Excellent video, concise and accurate. Honestly, brilliant work!
Absolutely amazing video!
Hey I met you on Saturday in cobo center
It was nice meeting you!! :)
+sung bin suh Great to meet you as well!
Great video, I love when those kids wonder in to hang out.
A very nicely made video. I need to learn to do this at work.
I would be interested in how that relates to off the shelf products. I have always thought there was a linear relation to resistance vs. grip. but this video was very informative to show both can happen. A series of videos on tires would be very interesting. Good video thanks.
Awesome video! I've always wondered about the magic behind LRR tires ever since I bought a set on a whim a few years ago. Their contribution to overall efficiency is minimal compared to the other resistive forces, but working as part of a system designed to be efficient, they definitely make a difference! Talk to any tech-savvy long-term Prius owner and they'll tell you all about their adventures with different wheels and tires. :)
A topic suggestion: I am interested in the science of "hard break-in" vs "normal break-in" of new vehicles. What's your take on it? I am sure it would make for a great topic for another video
Hey I gust got back home from that event! Our team did pretty well for a first time entry.
Interesting EE. I swapped out the stock Michelin tires that came with my FR-S for Michelin All Weather Super Sport tires. The mileage is slightly less than the stock Michelins, which were optimized for high mileage, but it is a good trade off for me because I like the handling of the Super Sports much better. And after all handling is what the FR-S is all about.
Awesome!!!!!! everything explained easy and quick. I was wondering if you can make a video to explain engine load ? There's many videos around where you plug in an obd dongle to display engine load in percentage and this info can be used to improve fuel efficiency. Great videos!!!!!!!!!!!!!
Ill take that 1 mpg hit over even slightly less grip any day.
Wow...That's pretty cool.
Nice video.
Whoah I was at the Eco-Marathon! I wish I'd known you were going to be there, it would've been awesome to meet you in person!
Very Informative video, glad you made a video that most didnt.
My AS3+ Michelin have silica compound. Great tire.
Great video, very insightful.
I learned about this in a lecture. The different energy loss factor of rubber in different frequency ranges is explained by the Williams-Landel-Ferry diagram - rubber with silica additive has higher energy loss factor in low temperature range and lower energy loss factore in high temperature range. I just can't figure out why braking (high frequency) corresponds low temperature.
Please make another video explaining role of rubber stiffness in transient speed conditions and its effect on rolling resistance.
Again. Excelent explanation.
+Pablo Guillermo de Oliveira Muro Thanks!
Thanks. I got it now why Firestone Firehawk Sport 01 (Bridgestone Potenza Adrenalin RE002 reincarnation) which has high rolling resistanse the same as RE002 has very high grip, but less fuel efficiency.
Very cool - Frenches rock! They are great engineers : )
Wow that was great innovation !!1
Very interesting!!! one think I don't know why happens is: why does a tire lose its grip while wearing down? doesn't the tires have the same compound throu all the profile? You can notice that more dramaticly in motorsports...
omg i NEVER would have believed it is less rolling resistance then a steel train wheel! that is almost unbelievable! wow!!
fuark even less friction than a train! thats amazing!
+Yang Yu How is that possible though? Is it because a train is inherently heavier and so the coefficient of friction naturally higher?
+rallymaniac92 trains have ridiculously low rolling resistance, there's a video on it by James may around youtube on "headsqueeze"
Haha I've seen that video too ;). I'm a huge fan of trains myself. Cheers.
The real question is can we have a high grip without having the life reduced ?
+GogogoFollowMe That's the goal. This is something Michelin is currently trying to demonstrate in Formula E, as they don't have tire swaps so the same set of tires have to last through practice, qualifying, and the race. I've spoken with a few team engineers and they say the degradation is very low.
+GogogoFollowMe I guess it would depend....
I drive a lot for work so I have two examples:
I have a sports car with very soft tires. At first I thought that they wouldn't last, but They lasted over 70,000Kms with a double wishbone front setup and multilink Rear RWD. ( Can't rotate due to the different front to rear sizes )
I also have a small hatch back with tires that were about the same 140 treadwear and they only lasted 40,000kms with a McPherson front setup and torsion rear... FWD and 1/2 the HP. ( Rotated every 15,000km) Still not that bad.
I also check and adjust the tire pressures weekly, so they are never low or high.
I assume that the life depends on too many factors, including the setup of the car, how you drive, types of road etc....
+GogogoFollowMe Well if you look at the 2010 Formula 1 Bridgestones, where the disbenefits of the tire degradation is less than the benefits of weight loss from fuel throughout the race (net benefit from the two factors), if my memory serves Sergio Perez ran 80% of the race on a set of Options in Valencia. Correct me if i'm wrong, but i do remember him racing a very long stint on one set of tyres. That's one mighty compound Bridgestone got there.
I think it really depends most on how you drive. I don't think that sort tires would wear out fast if people weren't putting excessive stress on them. If you increase the stress, you increase the wear.
There is no practical incentive to commercialize a high-grip tire with minimal wear. They want to make money. Their commercial formulas would be centered on some exec's cost-benefit analysis.
That's awesome! Any word on when this will become available to the public? I'd imagine it'll be pretty expensive for a bit until they're able to get costs down, though.
The tech has actually been around since 1992 when Michelin first invented it, but they've been improving it ever since, and it's transformed the industry as everyone now uses silica compounds.
+Engineering Explained How does the wear of the compound compare to earlier versions of radial tires? If it has high grip I would imagine it would wear quickly, similarly to a performance oriented tire but with low roll resistance I would imagine it may negate this effect of wear.
+Engineering Explained Sweet! Never knew that. Thanks for the awesome videos, Jason, and hope you enjoyed your time in my home state of Michigan!
Michelin is currently selling tires to the public with high levels of silica. The Michelin Premier A/S and the Michelin Pilot Sport A/S 3 are two examples. Go get them! I have the A/S 3 on my car, awesome tires!
Welcome to Michigan !
From what I remember from school, "Hysteresis is the dependence of the state of a system on its history." How does this work with your definition of hysteresis?
Michelin also makes special tires with low rolling resistance for Solar Car competitions (American Solar Challenge and Formula Sun Grand Prix). I'm on the University of Kentucky Solar Car Team and trying to get some for us, but they're definitely hard to get...
Are you going to do any videos detailing the individual vehicles that competed?
Interesting video, I didn't know about the importance of silica on the energy losses prior to this.
However his demonstration with the "silly putty" was innacurate, because it had higher losses at low speeds and less losses at high speed (opposite to what you explained in your graph).
+Richard Andersson Haha, everyone keeps mentioning this - at 4:53 he mentions that tires behave exactly the opposite. The demonstration shows that you can manipulate the behavior of a compound depending on the speed of deformation (frequency). Tires will have high energy losses at high frequencies (where as this 'putty' he's using does not).
Engineering Explained Sorry, I completely missed that. I would however be very interested in knowing why silica makes rubber behave the opposite. All normal plastics are viscoelastic (opposite to what you want in tires), such as rubber without silica, plastic bags or even silicone based compounds such as "silly putty".
please make a video on crawler gears :). and kudos to your hard work!
Based Frenchies. I really wish I could have had some high-performance summer Michelin's for my car, but they only had standard touring tires. They have top-teir all-seasons, but I was dead-set on summer tires.
How do the Shell Eco-Marathon tires achieve one-fourth the rolling resistance of steel wheels on steel rails? Perhaps the rubber compound deforms more than steel, but loses a lot less energy to hysteresis per unit volume deformation. It kind of checks out when you consider how low of a height a steel ball rebounds to when dropped compared to a rubber ball.
This was awesome! I wonder how significant the difference in price is... If a tire with this technology is much more expensive, it completely undoes the benefits of it lasting longer.
+Arthur Sperotto except if it saves your life?
Carl Head How? Is this tire somehow "safer" than a tire without silica? I'd love to know how.
Great video man!!
So, non-Newtonian rubber?
Also us older guys used to work on a 4 PSI difference between cold and hot. So if your tyres are inflated to 34 PSI when cold, they should reach 38 PSI when hot, and no more.
If they increase more than 4 PSI when hot, your cold pressure is too low and needs to be increased. If they go up less than 4 PSI when hot , your tyres were over inflated when cold and should a lower pressure when cold.
Car manufacturers usually go for comfort which is too low when cold.
Not sure if it applies nowadays. Replies welcome.
Excellent video! Well done. I have watched many of your videos, so i felt i owe you a subscription.
Please answer: What are the realistic and verified rolling resistance coefficients? or at least approximations. Train rolling resistance varies too much to get specific coefficients from the comparison. Are we talking about less than 0.001?
Just to set things straight, the silly putty is "exactly the opposite" of what the silica tire does.
And, the low frequency is the tire ROTATION at driving speeds; the high frequency is the IMPACT with the road.
tldr, low rolling resistance, high resistance at micro scale contact with the road.
So it's a non-thixotropic dilatant fluid? How does it keep its shape when it's in the tire? I'm assuming there are solid compounds in the tire material matrix that act as a clathrate with this new STF material and the two subset phase types (plastic solid/fluid) combined act as a Bingham plastic?
Great video, thank you!
the Michelin spokesperson is hologram!
Which tire would have high grip and low rolling resistance Is it possible in a summer tire
Nice video man! Shout out to the kids though. The one with the hat.... What is this guy talking about? Oh there's a camera. Other kids: WUT?
sorry for my English, but I wanna ask:
As we were explained, if we want low rolling resistance we need a tire, that is hard at low frequency deformation, so, it needs to be hard when you deform it slowly. From another angle, we need soft, elastic rubber at high frequency deformation, if we want to have some grip. It means that tire need to be soft, when it deforms quickly. BUT, what we saw on demonstration whit the sample of rubber is totally otherwise! The sample is hard, when deformation is fast and soft when it's slow. Won't the tire be high rolling resistance and with no grip, if it's made of this rubber we were shown??
Is there any calluclation or procedure to find out the rolling resistance when a body is in motion or when the body is about to start
in the video he said that silica are highly deformed with slow speed and dosnt deform or less deformed with high speed and he also said that in the car it's opposite so how we use it in the car
good INFO' good show.
So do all new tires have Silica? even the cheap ones too?
I don't think so, he says it's a newer technology, so I think it'll eventually trickle down to the cheaper ones.
I researched a bit and even Nankang has silica tyres already, but not for sale where I live :(
+Mortalomena that's a bit sad... Where do you live?
Samuel L.-Cloutier Finland
+Mortalomena Oh I see... Do you have better winter tires over there? Asking from Canada.
how can the rolling resistance even be 1/4 of that of a trains's wheels? steel doesn't deform almost at all.
I wonder if it is the rails deforming. At every track I've been around, you can see the ties moving and if the bearing structure is moving, the steel on top of it has to be moving as well.
Fascinating. I think I've missed or didn't grasp the concept though, regarding how silica's high deformation at low speed and less deformation at high speed (instead, breaking) helps maintain grip at high speed (frequency) while providing low rolling resistance at low speed (frequency). Wouldn't it cause the tire to deform *more* at low speed and *less* at high speed? Is that accurate?
Or is it that it deforms more while stopped or at low speed, allowing for traction off the line, but then quickly firms up and reduces rolling resistance once the tire is moving? So while it will perform better from a stop, it likely won't handle cornering or high performance as well as a sport-oriented tire (such as their Pilot Super Sport tires).
I spotted the exact same logic error. You want the tire to not deform when done slowly and deform when done quickly. And the exact opposite was demonstrated.
he sead in the video that their material do opposite thing that the material he just showed
The guy said the demonstration of pulling apart the silica compound putty shows the exact opposite effect to tyres with silica compound?? I'm confused - pulling apart the putty quickly (ie high frequency) leads to it breaking into two, but don't you want it to deform slowly at high frequencies to simulate grip?
that was pretty interesting, thanks.
based on the Michelin low rolling resistance tire I got, the answer is no. the tire was a hockey pock in rain
+Simon Zhao Hockey pucks actually have a pretty high hysteresis (and thus grip). :P
+Simon Zhao Well, low resistance tires grip will probably improve when this new technology comes to the market. But, I agree, for now it's better to go with a regular tire, not a fuel saving one. I can recommend Conti Premium Contact 5. Excellent wet grip, almost as good as when it's dry. Crazy really.
+Engineering Explained I meant like hockey puck on ice
+popula I can vouch for you, I have conti contacts on all four corners, literally amazing tyres.
It's like a non Newtonian fluid!
+That Guy With the Pointlessly Long Username That You Are Wasting Your Time Reading Right Now , i did not waste my time reading that +1
can you make a video and explain what you need to do to your engine when a turbo is install?
Get a tunable ecu to adjust a/f ratio, new MAF, bigger injectors(probably) front or sidemount intercooler for turbo, oil cooler, waste gate/turbo timer, blow off valve, upstream 02 sensor(s) and possibly bigger exhaust
So is this material not very wear resistant? Why aren't we seeing it coming to market?
wow it is good idea for the express
so for the silica tires, the hysteresis curve would be a function of frequency?
The tires have 1/4 of the steer wheels on a steel rail! That is incredible.
Interesting video.
One question: shouldn't rolling resistance be measured as a dimensionless number, rather than kilograms / ton? (A ratio of masses, doesn't make much sense at all, except that it's a ratio.)
I don't understand the stretching and then breaking the silica relating to a tire ? :)
Unbelievable .. i never thought something cud beat steel
Explain Egr and is it needed
does this help offroad tires as well
I still can't get my head around how silica can make the tire efficient. So it's efficient at high speeds then? and grippy at low speeds?
Hi, I am Abinash. This , video was really cool, but can you compare between these Michelin tyres and bridgestone ecopia(ologic) that was used in World Solar Challenge Australia 2015
I have a question how does this affect the sip angle?
but how much energy is spent on typical car with weight of 1ton to 3ton on rolling resistance ...
Thank you. Now my dog understands what hysteresis is.
+SomeTenth At least hysteresis in the context of energy absorption vs flex in rubber compounds.
+gerbizzlefoshizzle Yeah, it'll take him some time to get a degree.
why are these tyres still not in production then?
I have some michelin premier all seasons on my honda element, fantastic tire in terms of performance, but my god do they wear quickly