Understanding CVT !
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- Опубліковано 22 вер 2024
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CVT is used by the latest high performance vehicles due to the smooth driving experience it provides. In this video we will explore the inner workings of Continuously variable transmission including that of a Reverse gear.
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Again and again, want to say thanks to the people who make educational videos like these.
+huluminus We are happy to know that. If you want to see 2 video releases from us every month, please support us at Patreon. We desperately want to add one more member ( a video editing professional) to the team.
You're welcome 😊
Seems kinda like a boring thing yo.watch but glad somebody made this video.
@@Lesics Hi LESICS, could you please make a video explaining th3 working of a Toroidal CVT transmission
I appreciate the recommendation to another individual's video. This shows humility.
This is the real miracle of UA-cam. Learning this kind of things in such a cool way.
Wish we were taught in class like we learn things on you-tube.
You mean it's not for watching endless videos of famous/wealthy people reacting to other people who are commenting on other people's comments? Weird.
"You might be wondering how a reverse gear is even possible with this mechanism."
damn right i was
😂
@@fricken99 let us see your business card 🤨
It’s called a planetary gear set. The only reason it’s there is for reverse.
@@BikeStandByMe I'd be flintstoning myself backwards before I figured that shit out
The CVT is unique in it's ability to convert the power output of the engine into debilitating sadness.
I’m hearing a lot of bad things about it
@@iceyy8741 It’s mostly due to the reports of JATCO cvt transmissions being horrendously unreliable, (JATCO being a subsidiary of Nissan) and due to the fact that JATCO supplies a decent number of automakers with their cvts (IE GM, Chrysler, Mitsubishi, Nissan, Suzuki, etc) there are countless amounts of complaints with their cvts simply due to the fact that so many people are using them. Other companies such as Honda, Toyota, and Subaru design and build their own transmissions for their vehicles and receive little to zero complaints on their transmission reliability.
TL:DR; from what I can see, cvts can be great IF made properly!
only if you are the type that doesnt do any maintenace
its not that hard to change the fluid
@@sgt.scrooge4998 i agree
@@iceyy8741 yes..
Wow! As someone who went to automotive school and learned all about the traditional automotive transmission before this was a thing. I learned a lot in this video. In fact, this style transmission seems to be a lot simpler to understand once taken apart than a traditional transmission. Now, I just need a comprehensive explanation of how the Koenigsegg drivetrain works... without a transmission.
Direct Drive used by Regera, or Light Shift used by Jesko?
@@dbclass4075 he’s referring to the regera torque converter
As much as I don't care to drive CVT driven cars, this is genius.
Check the recall list
@@rockexpert is CVT that bad?
I am using manual btw
It’s not that bad, but some manufacturers just don’t make them well.
Andri Juliansyah As someone who owns a car powered by a CVT. It’s honestly not that bad. Transmissions die due to neglect and people driving like crackheads.
This is as simple as it gets. It isn't more widely used because that belt wears by the second. Want to see real genius? Look at an automatic transmission. That thing is complex and we'll thought, not this.
I understand it alright. I'm on my second CVT on my Altima
That's horrific, hope you're not having to pay for them😔!
Same, but with a Sentra. There are class action lawsuits against Nissan....look into that if you haven't already. I had to pay out of pocket for mine. I'll never buy another CVT.
Get rid of your Altima if everything is working on it
The only cvt that are somewhat worth a dam. Are Toyota and Honda. Every other manufacture outsources the cvt, so they have way more design flaws.
@@jerryvelasco1474 Honda's & Toyota's are now being designed in America; the result of a hostile take-over from the 1990's. GM, Ford & Chrysler needs to control what they're competing with. The whole automotive industry is a lost cause.
Hello friends, we hope you liked the video. If you want to see 2 video releases from us every month, please support us at Patreon. We desperately want to add one more member ( a video editing professional) to the team.
+Learn Engineering Does the person need to be in the same location as the rest of the team? I know a guy who does short-contract video editing, but he lives in Nebraska.
+William Dye We have an office space in India. Right now the total team size is just 3. We want to add one more member as a permanent employee. However Ad revenue from UA-cam is not sufficient for this. The donation can be as low as $1. Please visit our Patreon page
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plzz are you using catia v5 to design your devices ?
themyth553 We are using Blender
Learn Engineering L. , Kokomo,
K,koi,kkkopppppppppppppppppppppppppppppppppppppppppppppplpppppp
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Again and again, want to say thanks to the people who work at youtube . And people helpers who help educational videos like these .
Forgot to mention that CVT offers the most acceleration of any transmission for the same engine. Also, you could conceivably design a turbocharged engine with extreme turbo lag for the sole purpose of being coupled with a CVT. The turbo lag is irrelevant because the CVT will always keep the engine in the power band, no matter how small.
Not entirely true.
You'd still have some noticable lag for the first few turns until the engine is burning enough fuel. It's not an instant lag remover but keeping the turbo in ideal RPM WOULD eliminate lag after breaking.
@@SHDW-nf2ki True. There's also the other problem of mechanical power losses. If the CVT transmission is too inefficient, power will be lost at all speeds, eliminating the acceleration advantage of the CVT. And generally, CVTs really are less efficient than other transmission types.
@@J7Handle It's the most efficient transmission type because it's constant, or as the acronym says "continuous." The CVT itself is just another mindless transmission device like the gears on a mountain bike, all of which serve one purpose: Torque conversion. It's the Transmission Control Module (TCM) that runs the show. Am I race car wanting to stay in the powerband for fifty laps or am I road car w/ fuel efficiency in mind? It's the brains telling the pulleys what to do. As for turbo lag, that might be a trade-off because you could program the TCM to keep the revs at X to build up exhaust pressure, but that could conflict w/ a perfectly tuned CVT that just wants to stay in the powerband 24x7, I refer you to the Williams FW15C Formula 1 car. And when you say "braking" - well what are you braking for? A hairpin or a high speed kink? If you keep the TCM programmed for maximum turbo delivery you've got all kinds of problems w/ too much power in some corners and you'll be getting wheelspin. You can have all the power in the world, like the 1400 hp turbocharged beast, the Brabham BT52 (most powerful F1 car ever made) but that power was useless in corners, Nelson Piquet said you didn't "drive the car" you just hit the gas somewhere in a corner and if you timed it right the turbo engaged at the right moment for you to shoot down the straight part of the track. CVT maximizing exhaust pressure for turbo power in a braking situation might be counterproductive, depends on the situation.
Cope
Also forgot to mention that they all fall down and go boom faster than even the most american-made automatic transmission
Incredibly interesting and clearly summarised. Iv'e been a car tech for 12 years and never really covered or previously understood these systems, great video guys!
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I remember watching a repair training video on CVTs once. First thing they did was go over a brief history of it. Originally, the mechanism was constructed and used, in the late 1800's for newspaper print machines. I was thinking to myself, over 100 years, and they still can't get it to work right in cars. What a surprise.
they work fine, the operator or driver has to maintain them or else they break like every other machine
Unlike printing machine, cars need to carry tons of weight and move thousands of miles. It can work wonderfully in printing machine but not quite in cars. It's a bit delicate
You might be surprised they work on tractors - which carry way more weight and run for far longer than your car does - and do so for thousands of hours.
@@an2thea514most farmers I know can't stand the CVT's. They go for power shift transmissions instead.
@@mrsmith2876 I know farmers that also deliberately chose the non-powershift gearbox option when buying new.
But from the farmers I know, 20-70 years old, most that can, prefer CVT
Finally, I can go 100 in reverse!
Wouldn't recommend, I lost control of my first car after about 40 lol
@Tony Alston was just a stupid teen trying to impress a car full of high-school peers. Went down a road that ended in a dead end and thought I'd show off by flooring it in reverse instead of turning around. Went smoothly till approx 40clicks and then lost control, missed a parked car, ran up onto someone's lawn and smashed into a light post lmao. Safe to say my nick name was Parnelli after.
@@cadavher at least you are still alive :)
@@cadavher its good you've learnt from it though!
@@cadavher you’re a legend
Its amazing how taking simple concepts of the machine and turn into precision instruments to transfer power more efficiently.
I had an old moped from the 1960's that used a similar principle as this. As the engine RPM increased, some centrifugal weights would fly out and cause the front drive pulley to change it's diameter. The pulley was driving a rubber V belt that connected to another pulley that was mounted to the frame and directly connected to the drive chain. The engine was mounted on a spring loaded slide so that it could move to compensate for the drive belt getting shorter as the RPM increased and vise versa.
Thank you. Do you still have the moped for sale?
@@Andrewsky347 It is long gone. As I recall, the engine was mounted with one pivot bolt and a spring. The bolt never held the engine tight. There was no sideways movement but the engine could pivot backwards and forwards. When the pulley expanded, the belt effectively got shorter so, the engine swivelled backwards against the spring tensions.
I had an old scooter, a Manurhin Hobby with this system, it was a later model called a beltomatic and it had a contact on the pulley so that when enough revs were achieved just before the bike would move it would earth out the engine and as it was slowing down would cut in again and then cut out again repeating this until you were ready to go, at that point you would flick a switch on the handlebar which would allow you to bypass the earthing contact and thus get moving. I think the idea was to keep the bike stationary and avoid any mishaps when starting as it was a pull-start engine.
From the graphics I see that a CVT allows the car go down the road with only the front wheels turning. Amazing!
Nice animations.
+Physics Videos by Eugene Khutoryansky You here? This has nothing to do with QM, universe, electrons or gravity... haha.
how to replace the timing belt on a six cilyders Toyota Camry 2011
N64
i love you.you changed the way i se the world
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CVT is an example of a technology that's a great idea and theoretically better that what already exists, but is being unfairly held back and hated because a certain manufacturer is too cheap to make them reliable.
f*ck JATCO
Nissan?
@@ninosanvithian8116 Yes
So I could hypothetically achieve highway speeds in reverse? Interesting
Ethan Henry basically driving a forklift at 70mph. Seems safe enough😂
That's what I was thinking, maybe just by changing some code. Pretty cool actually.
You should check out "daf reverse racing" It's an old dutch racing series with DAF card that have CVT transmissions
yeah that's interesting. 007 and fast and furious now can use CVT to run back!
the Koenigsegg Regera can do something similar allowing backwards speeds (if unlimited) as high as its top speed
Holy crap, I actually understood all of that. Thanks!
I didn't want to.. It fucking appalling to drive a Nissan with.
Would you mind expanding on that remark?
ChumpyChicken2 No wonder. Nissans VCTS ARE CRAP. DRIVE A HONDAS CVT.
Mcig
I worked for Link Belt making single ratio industrial planetary gear boxes for 30 years, they are very strong and rarely fail, usually when they are run with no oil.
What were the gear boxes used for?
when that steel belt breaks , those small steel particles travel through out the transmission , usually in total destruction with little or no chance of a rebuild.
It's such a simple transmission. You don't rebuild them. You just replace them.
I appreciate the recommendation to another individual's video. This shows humility.
CVT transmission is there since a long time and used in different motorized vehicles such as snowmobiles and they used for a long time it's just now becoming huge in car industry and for sure it's improved since then . I have a toyota with a CVT in it and it have over 100k miles with no issues . And as all the other things in car industry that came new by time you won't notice it same like the electric power steering that all car have and no one talks about it
If you had a Nissan/JATCO CVT you would be singing a different tune.
@@oveidasinclair982 ive had a nissan cvt for 5 years and the only bad thing so far is hearing people on the internet complaining
I have a nissan with 140000 miles no issues
I had a 2016 Nissan Altima with cvt and no problems.
@@oveidasinclair982 because the cvt of a toyota and lexus are way differwnt
Because of this channel and Thomas Schwenke. I just learned how the Automatic Transmission, and the CVT both work. Along with how they shift so seamlessly.
Here’s what I have learned about cvt after driving one for 9 years. On the whole, it works great. I really never feel it shift. If I drive carefully, I can keep the rpm’s pretty constant while speed increases. There’s one thing I don’t like about it. Contrary to the advertisement, it doesn’t get the same mileage as a stick shift. The figures they give you are only on level ground with the engine and transmission fully warmed up, which takes 10 to 15 minutes of driving. In the winter in Wisconsin, maybe longer. I would see my range go from 450 miles on a tank in the summer to 350 miles in the winter. My previous car with a 5 speed shifter had nowhere near that kind of drop in efficiency in the winter. But all in all, it is still my favored transmission.
It never will. A stick shift is still more economical than any automatic in most cases.
@@ryanjonathanmartin3933 that's a myth nowadays. having an infinite number of gears (like in a CVT) fundamentally makes it more efficient than using only 5 or 6 steps. With computers controlling everything nowadays it's almost always going to be more optimal than a human
@@igvc1876 yes. I said "most cases", not all. I should've clarified by comparing manuals to older automatics, not the new ones. Sorry.
@@igvc1876 you are forgetting that there is less power being lost in heat from all the friction of gear change.
@@igvc1876 drivetrain loss is significantly higher in any type of automatic transmission other than AMT and dry clutch DCT, which is why new cars with manual transmission still consumes less fuel than their automatic version.
Sweet burnout at 0:01.
I don’t know about cars, but I love a CVT in any AG application. It’s great to be able to travel at any speed while maintaining engine rpms, especially when you need it at a proper rpm for hydraulic flow performance or PTO driven implements.
Slow down, there is another side of the cvt that isn't so nice. Get the full picture before you start throwing praise around.
My Dad has a hybrid, 2022 toyota (forgot the name). All I must say though is it's like a minivan with a 0-60 of 5 seconds and it's a joy to accelerate in. It is completely seamless and it's amazing how well it performs. This is due to two things (to toyota's credit). Custom made, in-house design and development of their own CVT, and the fact that for the first initial push, it utilizes the incredible torque of its two or more electric motors, which makes for an exciting experience in sport mode.
All hybrid Toyota use a planet gear to transfer /divide power between internal combustion engine, electric motor and wheels. They don’t have a transmission, despite Toyota call it e-CVT to avoid panic. It’s a simple structure without the ability to change gear ratio, hence extremely reliable.
@@ShuotongLi So the engine only sees use as a generator/launch gear then? Interesting.
What is more interesting is that the Toyota Prius is not a CVT type transmission as commonly thought. The gas engine and both electric motors are always directly connected to the wheels and to each other at all times through a simple sun gear arrangement. One of the electric motor determines how much power is being directed to what and what direction forward or reverse). The Prius is always in gear at all times, there is no torque converter or clutch to disconnect the gas motor or electric motors from the drive wheels (There actually is a clutch but it is always engaged at all times, it is not controlled, its only purpose is to absorb drive train shock). The Prius is always in the same gear, the same gear ratio at all times. there is no reverse gear. The gas engine can start when the car is moving forward or moving backwards. Basically the sun gear transmission is directing gas engine power to the wheel or generator or both, how much power is directed to the wheels by the gas engine and or electric drive motor determines the speed your going to travel at while moving forward or moving backwards, again no gear changes or gear ratio changes ever, its always in the same gear at all times, always 100% engaged, even when parked or in neutral.
So, how do you go in reverse?
ok but how do you shift then?
@@1mostwanted253 you don't ever. It never '
"Changes gears" allways in same gear, is always the same gear ration.. You have drive, reverse, hill (like a lower gear) and park.
No clutch, no torque converter...wheels reduction gear to sun gear to all three motors all the time. Simple and extreemly reliable. No low gear, no 1st gear, no 2nd gear, no third no over drive, no reverse gear ( when you put it in reverse no gear change occurs)
With wheels allways directly connected to all three motors (1 gas motor, 2 different electric motors)
Allways in gear even when stopped. Look it up, try googliing it.
Oh technically it does have a clutch but it has no controls and is sllways fully engaged, its only purpose is to absorb drive train shock.
@@1mostwanted253 a cvt doesnt shift thats the whole point of it.
What software do you use for animations? They always look amazing.
The most glaring issue for Cvt transmissions is well power is being put through a flexible metal Belt/Chain all the time. Anybody that has bent wires back and forth knows what happens it breaks.I say over 60 percent of cars owners never change there Transmission Fluid. Cvt transmissions have to have good,clean,cool fluid to work right.
Toyota has changed there Cvt transmission to a hybrid one they call a launch gear (2018 and up)starting out is where the most torque is forced through the transmission.If you want your Cvt transmission to last change your fluid to LUBE GUARD. Ask transmission shop about them. For the longest Sperm whale oil was used in Automatics it worked great and then in 1972 the endangered species act came law. Well they changed atf fluid and boom automatics were falling apart burning up. A scientist found synthetic replacement called a Liquid Wax Ester.
I have been using Lube Guard in all my cars and I have never had a transmission go out sense I have changed, they make protective Lubrication engine,transmission . I have a 2008 Honda Crv with 430,000 Miles and original Transmission , my aunts 2007 Maxima v6 with a Cvt and she has 230,000 miles on hers and never a problem , I should add that I installed a extra Atf cooler on both of them.I change my fluid every 20 thousand miles on her Cvt and in my Honda every 30 thousand. I don't recommend this with a normal automatic but if your Cvt is shuddering and acting odd order there fluid and use it , it could save you. Cvt transmission when they go they grenade in there boom metal bits and everything.
I was a good boy and got my transmission fluid changed on time ^_^
*their
Is Lube Gaurd safe to use in the Nissan/JATCOs that require NS-2 fluid? E.g. 4th gen Altima
Came here to regain my confidence back after watching the automatic transmission. Cause I can understand CVT.
It’s amazing to me they put together an entire video that doesn’t actually explain how it works.
As someone who's completely illiterate about cars, I did manage to understand very well how this type of transmission works. I, and a hundred thousands of other people, agree that this video is really very informative, so if there's any problem understanding the concept being taught in this video, it's most certainly NOT the content creator's fault.
omg a fwd and cvt bmw z4
With transverse Inline 4 Engine. ^^
Couldn't get more wrong.
Well, maybe mid engine that f*cker XD
@@davidguckenheimer8223 I noticed that too! I also just realized the rear wheels aren't even turning...
Of course the video is very educational, although I'm a bit surprised they make no mention of how stopping/neutral/idling forward works.
No comment
lmfao thats wut i was thinking
Don't forget, silly. It's a virtually computer generated car and model. Have you ever heard of programs like Blender, Brandon?
2 of the channels that I subscribed cooperated. This just got more interesting.
+Indra Ida Bagus Yes, we were discussing on this cooperation for the last 4 months. His video has more detail of the belt technology. He also explains how CVT is different in 2 wheeler and 4 wheeler.
what is the other channel?
CVT: "Continuing Various Trouble"
Absolutely, just to suck our money for a fancy drive that we don’t even need, then get stuck with difficult maintenance to go back to the agency.
Exactly!
Actually there are CBT‘s that have lasted a very long time and I have not broken yet like my one I made out of Knex
CVT my mistake
And you don’t need belts
After years of driving standards, I wasn't sure about moving to a CVT, but my Corolla SE 2021 has the Aisin Dynamic Force CVT, it's awesome on the highway, great pickup, smooth as silk, and it sounds great too, in Canadian winter and summer. You don't hear it all at any speed. So the exhaust has this low, basso rumble at up to 60 km/h, which I think is due to the resonator being right under and to the right of the driver, and then it's very quiet at high speed. Makes the car sound like a little Lexus from the inside. It's also got a single launch gear so that it has good pickup from stopping, then power is seamlessly transmitted to the pushbelt. It even has paddle shifting that simulates a DCT! Very pleasantly surprised.
Honda has a different cvt
I understand the CVT completely. I understand I will never own one, except in the lawn tractor.
If torque wasn't an issue for the belt, this would be amazing in supercars: Imagine something like a Koenigsegg one:1 with a max power output of 1,360hp and a max torque of 1,371Nm at 6,000rpm.
With a CVT that could handle it, this car could accelerate at 6,000rom constantly, meaning the full 1,371Nm of torque all the time (until it is on the highest ratio, obviously).
I imagine that as pretty awesome.
JustusLM I think most snowmobiles uses this too....
Koenigsegg has already accomplished something like that already, except without CVT.
They have designed their own single-gear transmission system from scratch, for the 1500hp Regera.
then imagine how full speed in reverse would be, with the origenal. going the same speed in drive and reverse.
Williams F1 car used such system and killed the competition, you can look up yt for that :)
@@rahulkulkarni3238The FIA banned CVTs before it could actually be used in a race
How to piss off all BMW drivers in less than 5 seconds.
I was JUST about to make a comment about there never being a FWD BMW and then I saw your comment.
i thought same as i started the video
you think so .. new one series and some of 2 series are fwd
I have some bad news for you..
.
matic šorn the X1 is also available in fwd 😭😭😭
Nice Vid its all ways surprising how some old tech just wont die. CVT's have been about for a very long time! I know the Daf 33 used two of them one for each rear drive wheel and no Differential also it could go just as fast backwards as forwards!
its scary going 60mph backwards, just sayin...
Nice explanation on CBT
The first time a saw this type of transmission was actually on an old Bridge port milling machine I used in college. The mechanism was so simple as the output pulley was just passively tension with a spring and would simply self adjust to whatever the input pulley diameter was set too by a handwheel which when turned pushed the movable side of the input pulley in with only the spring force on the output pulley required to keep everything in tension (though it is a very heavy spring). New machines like the one I have now use electronic speed control as its cheaper and more versatile but older machines obviously did not have advanced electronic speed controllers so the AC motor was locked to the AC line frequency and a transmission like this (also known as a reeves drive) was used to vary the spindle speed/torque while in operation. Except it sort of cheated because it also had a back gear on the output side to drop the speed range for more torque for heavy milling. Reverese was achieved with just a switch that swapped two of the phases on the AC motor so nothing complicated there. But ever since I have always loved this type of transmission simply for its simplicity unfortunately the reliability just does not scale up very well for the power demands of a vehicle even with modern advances in engineering.
tldr
The explanation is perfect. Well done.
People don't understand how much work goes into modelling, animating and rendering, an assembly in CAD. Kudos on this and thank you for the clear explanation.
P.S. Was this made in Autodesk Inventor?
All wheel drive with cvt is incredibly fun to drive my Subaru is set up like that and has plus/minus shifters. How that works I have no clue but its awesome
Everyone says they don't like these but I think they're good. It's true that the belt is the weakest part, but you can replace it in 10 minutes for $100. This is very useful on utv's and atv's where tow trucks aren't available and all the repairs you need to do yourself.
Not to mention these don't get you stuck in mud and snow because of the sudden power surge causing tire slippage other transmissions have.
Also I would like to mention something the video forgot to. They are AMAZING at going up hills. This is required on utv's and Atv's and just a bonus on ordinary cars.
The same thing was said when automatic transmissions known as slush boxes replaced manual transmissions. Some people do not accept change and progress very well. . I am surprised that we are not still riding horses.
pulley has different speed than belt !!!!
you have killed the science!
You didn't mention how a CVT handles neutral, or handles stopping at the traffic lights. What happens then?
neutral is handled in one of two ways, either a new clutch, or a set of tensioner bands like in a regular automatic.
Is that also what it does when stopped at traffic lights? It disengages a clutch? What happens when you first take off from traffic lights? How does it engage a gear ratio without stalling the motor at standstill?
uh. the same way you do with manuals or how its done in dual clutch transmissions automatically? you let it slip. there is no hydraulik converter like in most automatic transmissons
So does the car have an automatic clutch control mechanism? How is it controlled. That's not really been discussed in this video.
because thats not the point. its the same as in every car with a clutch. it slips then it locks up. automatically.
its still an automatic
I honestly appreciate a good CVT, they often got that little grunt of torque before sending me into revs POWER!!!!!!!
Also they are way better in snowy, icy conditions due to constant power = constantly controlled torque grip on AWD
It's like a vitech engine but built by mitsubishi and called mivec, completly underlooked but it's a master piece
for those saying CVT is crap, that's why certain CVTs include electronic manual shifts to achieve that manual feeling.
Speechless !! just awesome . Please keep up this work . Thousands of people are learning from your videos .
would love to see a dual clutch transmission video from you guys, your videos are great :)
as amazing as this is, it's not yet been proven in the real world, they break down too often and cost way too much to repair. If i ever get one i will wait a few more years before the bugs are worked out but for now i'm sticking with my manual 5 speed. 185K and still going strong.
I have one in my Mistubishi. 75,000km and not a single issue.
Can agree cvt’s are complicated to repair and tune, but there are plenty of motors that have had a cvt tranny successfully hah.
It depends on the manufacturer.
I read somewhere that manual transmissions will no longer be an option in the very near future.
I hope it was B.S. because I LOVE driving manuals.
Forward gearing = Sun gear directly connected to Ring gear and planetary gear systems act as single unit thus moving input pulley as same direction as input shaft
Reverse gearing - Sun gear is connected with planet gears thus obtaining reverse rotation with respect to input shaft...
Neutral = it is achieved by releasing both clutch and allowing the sun and planet gear to move freely
Input Pulley and output pulley diameter changes thus obtaining different speed ( diff gear ratios)
Genius idea for transmissions in things you're not supposed to enjoy driving. Seriously, though, this was extremely educational. Thank you.
GREAT VIDEO. The graphics really makes it easy to understand how a CVT works.
I enjoyed your presentation, even though I already knew how they work. The CVT is an interesting concept, but I still have reservations -- perhaps outdated -- about its longevity, compared to a more conventional planetary gear automatic.
things dont seem to be built to last anymore . but also it's hard to get the best possible performance and the best longevity out of components. cant have both . but trying to meet in the middle would be a challenge
In my Honda Insight when I slow down I feel like gear changing everytime with a little vibration. Why is that
That’s actually such a good idea, the automatic is so confusing so I might not see how genius that is too
This quite literally uses automatic techonology using the planetary gear system
best youtube channel ever.Hats off to Learn Engineering.
That's so generous of you to post this video 📼, many big Thanks dear
It's a well thought out transmission design with two huge flaws. First, it's very heavy compared to a standard auto of manual gearbox. Second, if the belt slips even once, its toast. Worse than that, it will be an exchange to get another unit since no one in the auto repair industry can touch the parts at this time. This means big money to replace.
So basically, this is why the main place you will find CVT is in lawn tractors. Cars are less common because of the stress, right?
Okay, I just came here to comment on one thing.
A FWD BMW Z4 with a CVT?
Ugggghhhh WTF?
Thanks, purchasing my 1st CVT - Nissan Murano.
Although people are leaving UA-cam in droves because it has become infested with clickbait, publishings like this will help it survive a bit longer.
Not only clickbait but also blurring,surprised they did not blurr parts of this.
What a great car!
One wheel is moving and nothing inside the hood except the gearbox 👌🏻
For those who say CVT is no fun, remember what is fun to you is not fun to another person. Fun is a subjective concept.
To some degree it could be seen subjective. But when it is generally agreed upon that something isn't fun then, one persons opinion isn't valid proof of somethings level of "fun" . Also a small child finds peek a boo fun, while adults would say its not even really a game. So maybe if someone considers a CVT fun, rather than see it as subjective, it should be seen that said person must rarely have actual fun if their threshold is that low. In which case I don't feel the need to empathize, but rather pity you or anyone that has that low of a "fun" threshold.
CVT is only fun to - 1.Those who have never driven a manual, 2.Those who are too lazy to drive a stick and 3.Those who don't want their friends to know they can't drive a stick. Overall, stick is more fun because it requires skill, concentration and quick timing, it tests the driver further. And all of this is generally agreed by drivers.
Aritra Kar Exactly, instead of hating on things you dislike, go with what you like. Not everyone is into cars and horsepower, some people buy cars just to get from point A to Point B. Simple.
Agree.....and where does it say driving must be FUN ? I drive to get places. Period.
@@aymaankhuraishinot defending Shit-VTs, but i want to focus on driving and not getting myself or someone else killed, rather than looking down to shift and fiddle with my gears. Thanks though.
1:20 - correction - it should be right side of the input cone moved to the left
Scooters are using CVTs to this day, although more to keep costs down by simplifying the vehicle. The key components are the belt, the variator weights and the clutch. If the belt has too much slack or is drum tight, then it won't work at all or perform poorly. If the weights are too heavy, then the vehicle usually accelerates quickly but suffers a drop in performance and takes longer to reach its full power. Too light weights can result in the variator never forcing the belt up all the way. If the clutch doesn't work properly, then the power isn't transmitted to the wheels.
I know that CVTs in cars are far more sophisticated, but the basic principle remains the same.
Are these generally more reliable than those in cars?
It´s incredible how CVT´s are easier to understand than classic automatic transmission
And it's also amazing how they last less than half as long too. Mine didn't log 159,000 miles before it went to hell in a bucket.
Best animation for cvt.. esp the markers on the pulleys indicate the turn ratios. Markers on belt helped to understand the reverse gear properly.
Dom can run reverse at incredible speeds. I think he hacked the programming of his CVT!
They are clever in theory, but crap in practice. ....the end!
Remember the DAF Daffodil? CVT transmission that could go as fast in reverse as forward?
you have clearly never riden a atv/snowmobile
Give it time. Automatic transmission also once inferior to the manual.
sovanndara soun The regular geared Automatic Transmission will always be superior to ShitVTs, and that’s the end of that story.
Lexus made an eCVT.
Just a 2 stage ECU controlled planetary gear set. Reverse is handled by the electric motor.
No belts and pulleys,but I think they went to conventional CVT,but with a "launch gear"
omg the guy who though of this is a genius
look up automatic transmissions, those things are so ingenious.
thank you for explaining the CVT transmission used in the front wheel driven version of the BMW Z4. The more you know
Cars with these are the ones that end up at the junkyard after 10 years since new.
Say it! It needs to be said to spare the innocent of this nightmare!
I think it's a lot sooner then 10 years
is that a FWD beamer...
kill me now
That was my first thought too. They could have used a Golf instead haha
he had 1 job
I guess they didn't have time to focus on the specifics of the car animations as the animation of the transmission is of a higher priority.
And transverse engine in BMW, great video but this just hurts my car focussed brain
Just imagine it is an 2 series Active Tourer, which is a transverse fwd car.
So this is just like how my 50 cc scooter works . Except for the reverse gear
This planetary system for the reverse gear seems really expensive and heavy considering its only used for going in reverse!
I think Hybrids should ditch this annoying part and only use the electric motor to go reverse (If the battery's dead it can always be recharged via the motor). It can same lots of money, weight and space. What do you think?
I would think an electric motor that is powerful enough to move the vehicle in revers would be much heavier than the planetary gear set.
I'm talking about Hybrids, who already have an electric motor. Most Hybrids already use CVT (If not all of them, besides anomalies like the Golf GTE) to reduce gas consumption so this is applicable in many cars.
That's a GREAT idea.
It isn't expensive nor heavy. It's build is very simplistic and cheap compared to far most conventional mechanics; it uses straight tooth gears ffs... Your idea would require an additional clutch, unless you restrict the electric motor from going into neutral and fix it after the clutch.
My friend was just telling me that his Prius uses only the electric motor to go backward. I think it's a 2013 or so?
Excellent video. Thank you!
what a great video. simple and elegant. Fully learned!
What this video failed to explain is that when a CVT unit fails, it will cost about 3-4 times as much as it cost to repair a conventional transmission.
Must have a warranty or extended warranty.
It dose seem to be more simple
Why would that be in an engineering video?
if you have a scan tool and tools and a garage and some patience, you can fix these
So dick you expect them to put repair price of everything.
damn i completely understand it now :D thanks!
dumbass
Yeah dumbass
high failure rate with belt cvt, E-cvt is the best no belts ex:Prius
Its crazy how many people have a cvt trans its different thats what that's what's so unique about it
One of the problems of CVT is that you can't use it with any kind of high horsepower or high torque engine. You never see V6 or V8 engines with CVTs.
In CVTs, the tensile strength of the belt, and slip between the belt and wheels, limit the amount of torque that can be transmitted. Thus, you have to stick to relatively small four cylinder engines.
How pully changes diameter, how often to change oil in cvt,how much cost replacing chain,
U cant change the belt. U have to rebuikd the whole tranny from the dealership :(
@@spongeblobsquarepants9819 that's bullshit.
@@ared18t They don't change the belt. They replace the transmission.
Good video, ... A smart man once told me, a high IQ , doesn't necessarily mean you're smart, just that you want to learn...
+SV867 ....your first book, should be a dictionary then, my friend...
well by definition IQ is your capacity to learn new information. Doesn't mean you use it wisely
The True Basis for High IQ is a Greater Ability to Assimilate Knowledge, and the Ability to Understand and Use the Knowledge you learn, it does not mean you are Smarter than Any one, Only when Common sense is applied to IQ then you have the ability to be Smart .
The Lexus LS600hL has a CVT, it drives like you're in the air!
That's because it's a Toyota, they make the ONLY reliable CVT on the market, everyone else makes JUNK, especially Nissan.
This is absolutely GENIUS. Man, things like this are an engineering marvel. I wish I had taken up mechanical engineering. The belt worries me yes but surely they can fix that or make something even more ingenius than this belt system.
My 2016 Nissan altima went into fail safe mode. Took two months to get it to slip back into normal state without replacing it. I posted about it too if anyone is in the same predicament.Now I am back breaking the sound barrier on the freeway 🥳🥳🥳🥳🥳
think simple, why some cars such as bmw m3, porche 911, camaro, mustang, etc. never adopt cvt. Belt and poly in cvt are not really reliable when high torques are transmitted. cvt is an awesome device for production cost saving.
이대성
They’re best for low powered cars, like compact economy cars, but shouldn’t be put in something like a truck, they’ll be destroyed.
is CVT reliable ? most of the Honda's and toyota's are equipped with CVT transmissions now.
Ask scotty kilmer
All cars will eventually go to them.
I would take a wet DCT ( Wet dual clutch transmission) anyday instead of CVT. I hope they become mainstream in the future.
whats a wet dct I know what a dual clutch transmission is but what is a wet dct
does it have a torque converter?
@@Silverdev2482No, it doesn't a torque converter. It is lubericated by oil so it doesn't overheat or wear out quickly like the dry clutches.
Dude, a fast reverse gear is GOD SENT. People should look into that. Like the swedes made a plane that goes in reverse just as good.
2 reverse gears. Will it add that much weight?
I have this in my Suzuki burgman 400 scooter,very smooth