IVT is the fully automatic CVT, and goes down to an output of 0- this means that the transmission is at an equal ratio, therefore at this output your pedaling is the only thing powering the wheel. I don't get why more bike use this. I've thought for hours and cannot think one reason this isn't more efficient than traditional set gear ratio bikes. Plus when you shift, the gear meshes always, so it doesn't slip, I beleive
@whoseline4gp Hi, CVT stands for continuously variable transmission not automatic transmission, you can have automatic CVT but it is not inherent in CVT design, hope that helps?
It's about 20 x the cost of a rear cassette, chain and chain rings.
Put them up for a retail price of $120 Au - with hydraulic // chainless drive - with a 100,000 Km warranty against internal failures, and I will buy one.
Great transmission. The main problem that I see is that it's hard on the balls (lol). Lot of friction, and probably isnt usable on anything larger than a bicycle
Is this unit sealed, or what will happen in a wet environment?
I want to use your transmission for a super high mileage amphibious vehicle I'm working on for college, but contrary to what your video claims that "this promises to be the most practical and ECONOMICAL cvt", I can't afford one. It costs more than any other component in my plan, and I'm just a student who already can't make ends meet with todays economy. Contact me if you can spare a second hand unit or demo or blem or ?
Using a non-Newtonian fluid within the walls of the CVT must mean that the quantum indifference of the rolling friction dissipates huge amounts of nebulation energy (at least a factor of 0.1)
@AVCheerst No doubt! Slippage of the balls must cause a large energy dissipation!
Nevertheless, take a look at this generator, it uses an Toroidal Continuously Variable Transmission, that is a slight variation of this one. And this video shows how it works in a high torque environment:
Not even considering the slippage issue, what's the range on this thing from low to high? From the demo it appears that the range would very limited and if that's the case why would I want this on my bike...unless I live where there is nothing but flat land all arould and in that case I would need only one gear anyway.
A bicycle is efficient thanks to it's simplicity, lightweight, no need for additional substances, and totally dependent on your own legs . If you start adding balls and oil to that, you lose the meaning of using a bicycle.
@ermalkoci Wait... seriously? You never wash your bike, you never clean/oil your chain, never grease your bb? Or, if you don't, those guys racing accross Europe aren't using bikes, but something so convoluted with external BB's, carbon fiber (with the included carbon paste for contact surfaces) fancy gearings, and such? Ok. Go back to your single speed and enjoy being on your soap box.
@FranktheBBB ye I see a BIG problem with this, although i have not used this, I would image it has a fair amount of slipping going on, meaning torque transfer is dramatically reduced, which is not good enough for pedaling up hills or using low gears. Is this what you experienced? I wonder how they will attack this problem,
Yes, I ride a busettii Big 50 Mile Bike ! I have had it for 3 months and it is great. My friends have other e-bikes but they are way slower and wimpier than my Busettii. I can get up to 60 miles on one charge and the top speed is about 27 MPH but they are selling at just $1700 now. BECAUSE OF THE BIKE paths and the right shoulder of the road I can go faster than cars across town. I want to try Busettii's new VORTEX mountain bike soon ! It goes 85 miles on one charge. ciao
@SamuraiClinton The fastest human powered vehicle goes over 80mph, it was driven by Sam Whittingham. Combination of recumbent bike, streamlined fairing, and LEGS OF STEEL, all made it possible.
@foxtrotHQ Like the "silly-putty" I remember from the science museum.. Pliable like putty if kneaded slowly, but would shatter with sudden impact, then return to being pliable.
If you dissolve corn starch in water to a very thick consistency the fluid is liquid when no pressure or immediate force is applied to it . When you apply immediate force it turns solid ! You can make it in 2 minutes. It is a very unique property. It is similar to the lubricant in this cvt
give me the good old chain and sprocket no energy losses this trany like a torque converter in an automatic car transmition has to much losses.for people power
@GLOCKIOMM there is actually plenty of energy loss in a chain and sprocket system, with all the hundreds of tiny "bearings" between the links, and the bearings that the axles have to ride on, this design by itself will definitely increase efficiency in almost any system it is properly applied to.
@MrMeanderthal That is a very good point. Apparently I wasn't really thinking much when I posted that. I was actually considering this for small-engine applications (chainsaws, go-karts, scooters, etc)
@meandmyevo there is larger versions of this device that will handle larger power input.. not sure how big they get but something in the range of 5 hp is already available..
@MrMeanderthal the design doesn't really limit power, just torque. if you had an engine that produced 15lb-ft of torque at 30,000+ rpm, that some seriously usable power that almost any tiny tranny could handle.
Actually, according to the exhaustively researched book Bicycling Science, and also the 1896 Bicycles & Tricycles: A Classic Treatise on Their Design and Construction, there isn't "plenty of energy loss". The chain-and-gear drivetrain has an efficiency of up to 98%. Nothing comes close to that.
And please, people, there are no "sprokets" on a bike. They're called gears, in general; "chainrings", up front, and "freewheel", "cassette", or "gear" (for you fixie fans), in the back.
This is actually a terrific idea! However, this should definately be used in vehicles, whose automatic transmissions suffer from significant losses in friction. Meanwhile, bicycle chains are VERY efficient, will rule all high-performance bicycles for decades to come.
@swamper777 There are CVT transmissions in some cars. A friend of mine had one and he said it drank the gas because CVT transmissions are very inefficient.
He said CVP at the end i think (2:48) - Am i missing something?
And also, I imagine this would let the pedel move if you were resting your weight on it while waiting to go at the lights - unless it has some kind of centrpetal-force-activated gear lock for when your not moving
Also, I would prefer a CVT that automatically increased its gear ratio with increased centrifugal force - which I think was the original design goal of CVTs (Am i wrong?) +Compensation for your prefered cadence
CVT are old school. Even with the dilatant fluid, I would of expect more friction than internal hub gear, unless the chemist have recently synthesize a ultra thin & thick viscosity liquid.
I will be impressed if such variable gear in a meshing gear format were possible.
@Guesswhokk It might even be possible to achieve this with ferrofluids. By using magnets you could vary the viscosity within the casing just as a STF would, and for torque you want resistance. Still, I think STFs would work just fine, you could get constant torque by compressing the chamber at low revs and higher torque naturally at high revs, for cruising open up the chamber even more at high revs for minimal resistance. This CVT is basically a variable torque converter.
@dragonamt The contact fluids used in here are already EXTREMELY difficult to formulate. I cannot imagine(if it's even possible) how complicated and temperamental a fluid with both of those characteristics would be to produce...
@GRAHAMAUS So... of all the hundreds of Subaru's I've torn into, I have never seen a solidifying traction fluid, nor have I seen a fluid that responds to magnetism in any way. What LSDs on which Subaru vehicles are you talking about?
I don't know about anybody but I understood almost everything except when the narrator said 2:00 "As you can see... there is a microscopic space" blah blah - fluid being solidified. I think this is a Hydrostatic design but the video sucks at explaining that portion of the fluid mechanics.
It's a unique design. I would not go as far as saying that it has ratios as in a 12 speed mountain bike sense. Since the balls or spheres are all the same size, the ratios are determended by the amount of viscosity contact pressure between the hubs via the spheres. Low gear would have the spheres further away from the output hub, therefore the fluid would slip more easily through the micro-gap.
It is efficient and works well on a small potable generator. So far.
@cobalt120: The balls engage the rings at different "latitudes" on each side depending on their position/inclination; at one extreme one ring will contact close to the "pole" and the other close to the "equator", thus showing different radii to both rings; thus, the ratio would be something like R(left half) / R(right half). The total variation between the highest and lower "gear" would be (Rmax/Rmin)^2, which depends. on how much you can tilt the balls.
It does not seem *horribly* inefficient, and I have seen at least two long term reviews in this thing. One using it with lower gearing than advised by the manufacturer, and pushing 2 kids for more than 10.000km in the space of 1.5 years. No maintence, and the hub aparently feels as new.
It was definitly over enginereed, to suport up to 5kw of potency.
@Paxmax leaks can be dealt with, but the wear... yeah... i was just thinking - what are these spheres made of, and how often do they need to be scrapped?
The torque is transfered via a fluid that changes viscosity(hardens) under stress of being forced between hub and sphere.
I think the problem is the dozens of brearings that holds the spheres.
The spheres will exert both axial and lateral pressure + the fluid must NOT leak into bearings or they will practically seize up (the fluids viscosity under stress ya know).
i'm sorry, but... unless i'm missing something fundamental here, that doesn't make much sense... if the fluid can transfer torque, it does so via exerting pressure on the working surfaces... in other words - if it becomes hard enough to transfer torque, it's hard enough to cause wear... just because we're dealing with fluid, doesn't mean wear is eliminated... hydraulic system components wear out all the time, right?
Sure hydraulic components wear out. But it is 99% of the times the seals onto moving surfaces.
The hoses doesn't 'wear' out from the liquid inside rushing by, they usually dry out or wear out in joints due to material fatigue induced by pressure shocks.
As long as the solid spheres doesn't touch the solid hug the wear is entirely negligible.
However adding a contaminant of a solid material like sand or hard metal will increase the wearing by a VERY large factor.
i guess you're probably right about the hydraulic thing, however that may have been a weak analogy on my part... in a hydraulic system there is no direct torque transfer... i mean it's not actually relying on traction between two solid components, like this variable transmission does. i mean... it planely says - the liquid momentarily becomes a solid... solids rubbing against eachother? i just don't see a way for this to be frictionless (or have a low enough amount of friction). traction = wear?
Well, it never turns into an actual solid, just a high viscosity. If it would turn solid it would JAM the mechanism as soon as it gets moving.
I'm guessing the effect is like corn starch and water. If you add enough corn starch to water you can walk on it as long as you keep moving. If stop you'll start to sink.
As for wear, you can eat your way through a thin sheet of steel with erasers, but it will take 100's of thousands of hours to do it.
With gravel pebbles it might just take you an hour.
well ok, again... to whatever degree it solidifies, that's the degree to which it's effective as a transmittant, and that's the degree to which it's going to cause traction/friction/wear... btw, i'm not 100% on this, that's just what seems logical, and i'm only pushing the issue because i want to understand it. and going with your eraser analogy - motorize the eraser, and trap the particles at the grinding point within a high-tolerance mechanism, and i think you'll have problems very soon.
I mean this in the nicest of ways, but if you're going to infer that there's wear, then you're inferring it's a real word system. Of course it's going to wear, everything does. If it was JUST metal on metal, it'd wear out QUIET fast in comparison.
I mean this in the nicest way, but if you're going to be unnecessarily verbose, at least proof-read before posting, so you don't come off as some half-literate windbag trying to sound impressive while pointing out the obvious. Also, I'm not inferring anything. This isn't the right situation in which to use the phrase "If you're going to infer..." If you think back to the coffeeshop/party/tvshow where you heard someone say that, you'll see that that situation was QUITE different from this one.
Hmm. Okay. No offense taken. Insinuating I THINK was the word I was looking for. Oh well. No harm, no foul, and we both know what each other meant and, as far as I can tell, learned just a tiny bit.
There was oil leaks problems with the first bacthes, but the manufacturer seems to have replaced the problematic units, and in the new ones don't seem to have this problem anymore.
Also, it is impossible to service it. It is sealed for life with an guarantee of 6 years (and from reviews it seems that it will last an lifetime for regular use)
Porque no usar una en veszde pelotas un disco que jire y que se mueva a los lados , haci da la reverza y la primera o segunda o tercera segun los giros? Con un buen lubricante.
It is quite easy to find this information.. Anyway, the weigth is ~4KG (competing hub gears are 1~2kg); it seems to be ultra-durable, even puting 1kw of eletric power in it; it is impossible to service, sealed for life with an 6 year guarantee; the manufacturer will not disclose the efficiency, but at the same time it don't seems to be too low. Probably at the low's 80%s. That may be compensated by your legs/motor working always at it's peak eficiency, so not that of a big deal.
The shifting of the ball acts like the different size gears... dunno why you don't get the rest, it's simple to me. I just see alot of issues with leaking, and weight. but then I guess the balls could be hollow. although I see the application on heavier vehicles, it seems like alot of device to replace the simplicity of the common gear system on bikes. but I guess its a novelty some might just have to have...
Not a novelty, for bikes, but the problem is weight. See to ride a bike at maximum efficiency you should ideally pedal at a set speed and decrease or increase your moving speed by changing gear. EG spin your pedals at 1.5 times per second and change gear to change bike speed. This is the most efficient way to ride a bike and racing cyclists would love it. The downside is that if the thing weighs 4 kg it is too heavy for a bicycle.
The circumference of each ball is biggest at the center and smaller near the ends. So, turning the balls at the same point from the center is a 1:1 ratio. As you move towards either end, then one end is spinning closer to the center (a greater distance) and one is spinning closer to the end (a smaller distance). This causes one end to spin slower (or faster) than the other end, giving various gearing ratios.
probably not. Then again, if a regular gearbox develops a leak and you don't notice it in time, you'll need to call a towtruck as well (or in case of a motorbike : push it home).
nice idea, the basic design is simple in mechanical terms, but unless the internal parts are made from very strudy components, it would wear out very quickly!
@500group: boy, am I glad I didn't know this thing couldn't work before I went out for an hour long ride today on my spanking new Crescent Nuvinci. I'm no expert, but there was not the slightest sign of the extra friction you guys claim. No slipping. I never noticed the weight either (but now you said it's so heavy, I'll think about it all the time). For all others, rest assured, it works. The "high friction" if it's there at all, is much too small to be noticed even by my lazy legs.
the bottom line is its just physics, the nu-vinci will always require more pedalling effort and that is a big deal for certain conditions, for a trip around the corner not a problem for a long ride big problem
so the nu vinvi may find an application for casual biking over a short distance
it may be more reliable who know although the plates need constant pressure on them and may be prone to slippage up hills etc certainly deraillers are horrible when it comes to reliability also
the problem here is friction not belts chains balls or anything else.
a chain and derailler allows the least friction, the nu vinci generates substantial friction relative to a chain and derailler (or a toothed belt and derailler for that matter)
we have the VARIATOR already, variators can also be made manually controllable, so only really new idea in this nuvincy cvt is that its planetary and probably a little more compact..
This is seems functional, i just wish they figured out some kind of spinning weight system to figure out how hard your pedaling and smoothly shift its self so no need of extra levers or anything on the bike. If shifting was automatic and always required similar pedal pressure every bmx rider would use one of these if the weight was reasonable.
Nice, This is a good idea, give it a few years to work out all the bugs. then it will be in alot of stuff. But it still it is not fuel efficient. like the auto trans compared to a stick. the hydraulic aspect is good for comfort but not efficiency.
Currently CVT transmissions are the MOST fuel efficient transmissions made for over the road vehicles. It allows the vehicle to select the best drive ratio for a given circumstance. This transmissions along with lock up torque converters are much more efficient than both manual trans and traditional automatics. CVT transmissions are standard on most new Nissan, Saturn, and most of the hybrid vehicles on the road and probably many more.
this is a friction drive and therefore no good for bicycles as it will rquire more pedalling power as some of that power has to be used to force the ball against the plate that is no good ! chains are way more efficient
it might be good for cars or small engine vehicles like scooters. but i think ur right it will not be good for bikes as there will be some slipping likely and powerloss.
Then why do many motorcycles use belts? Why is the new Soho using a belt? Chains are not better then belts,, they are, at this point, equal. Buy while chains have maxed out there potential we are still seeing improvements in belts. Same with this thing...yes it weighs a fair bit but technology can work out a lot of that, and the other flaws. The ease factor, and the infinite gear possibilities make up for it...at least for me.
Great design. Thumbs up!
Rotitomato 2 weeks ago
Can the gears on a bike be shifted electronically, via servos, as a full automatic? Just put it into "drive", pedal and forget.
ChrisHenniker 2 months ago
@ChrisHenniker watch?v=cd2-vsTzd9E
IVT is the fully automatic CVT, and goes down to an output of 0- this means that the transmission is at an equal ratio, therefore at this output your pedaling is the only thing powering the wheel. I don't get why more bike use this. I've thought for hours and cannot think one reason this isn't more efficient than traditional set gear ratio bikes. Plus when you shift, the gear meshes always, so it doesn't slip, I beleive
masterwolf1212 1 month ago
BALLS! that's all i got to say
GUYANESEGT 3 months ago
Well, that's rather interesting. I wonder what advantages it has over a traditional transmission. Is it more durable? Cheaper to make?
JuryDutySummons 3 months ago
all MTB'ers should have constantly variable rolling balls.
desertsongtv 3 months ago
It takes balls to do it :)
sourabharsh 3 months ago
Seems like the small area where it touches would just slip.
timerider4 4 months ago
What can i exspect from a supplier called "FAILbrook" on youtube?
zawzero 4 months ago
So what kind of inefficiency can one expect to see compared to a manual transmission?
johannthebored 4 months ago
And another one link to recent paper
iaengDOTorg/publication/WCE2010/WCE2010_pp1179-1184.pdf
minorlogic 4 months ago
I get that it will be smooth in transition, but how is it a CVT if you have to shift?
whoseline4gp 4 months ago
@whoseline4gp Hi, CVT stands for continuously variable transmission not automatic transmission, you can have automatic CVT but it is not inherent in CVT design, hope that helps?
cannissolis 4 months ago
the balls are inert.
r00dd00d 5 months ago
Perfect bicycle transmission
mech-ing com/journal/Archive/2011/2/129_Konstantin%20Ivanov.pdf
minorlogic 5 months ago
@minorlogic Maybe, but I expect the losses may be higher than gears so more pedaling energy turned to heat,
I would like to know the efficiency, gears run about 98%+ efficient
cannissolis 4 months ago
@cannissolis You can find all required info in
mech-ingDOTcom/journal/Archive/2011/2/129_Konstantin%20Ivanov.pdf
wwwDOTmadbassDOTnarod.ru./
The efficiency is close to efficiency of Bearing on high speed, because all gears is connected.
minorlogic 4 months ago
Scheme of the differential variator.
1. Input power is divided into 2 flow through a differential.
2. Flows give a different ratio (up/down)
3. Combine two power flow through the second differential.
Remembering that the planetary gear reducer and at the same time differential, we can build the CVT only with two planetary gears.
It seems, and the range and efficiency and capacity of the variator at much higher used in automobiles.
minorlogic 5 months ago
Lower Cost - my arsehole it is...
It's about 20 x the cost of a rear cassette, chain and chain rings.
Put them up for a retail price of $120 Au - with hydraulic // chainless drive - with a 100,000 Km warranty against internal failures, and I will buy one.
callmeshane303 5 months ago
oh just go but your balls in a transmission quit watching this
superdude4222 6 months ago
Great transmission. The main problem that I see is that it's hard on the balls (lol). Lot of friction, and probably isnt usable on anything larger than a bicycle
Here's an omni tire using same idea, search for
Single Omnidrive Platform v.1
thefatmoop 6 months ago
Brilliant - Well done
mobayguy 6 months ago
Yeeeee.... You invented clutch! :)
joviczarko 6 months ago
Is this unit sealed, or what will happen in a wet environment?
I want to use your transmission for a super high mileage amphibious vehicle I'm working on for college, but contrary to what your video claims that "this promises to be the most practical and ECONOMICAL cvt", I can't afford one. It costs more than any other component in my plan, and I'm just a student who already can't make ends meet with todays economy. Contact me if you can spare a second hand unit or demo or blem or ?
oregonmeds 6 months ago
Using a non-Newtonian fluid within the walls of the CVT must mean that the quantum indifference of the rolling friction dissipates huge amounts of nebulation energy (at least a factor of 0.1)
cdoftx 7 months ago
@cdoftx what... english plz
awsomeisepic 7 months ago
Got this though my friends email being hacked
dazipro 7 months ago
I wanna see that in connection with a v12, have a feeling the balls will pop
Antimeasure 7 months ago
блы всё на анлийскком не качайте ни чё не поймёте!!!!!!!!!!!!!!!!!!!!!ху*ня
KASUS4444 8 months ago
Does this not have a big loss?
AVCheerst 8 months ago
Comment removed
arielvollmann 7 months ago
@AVCheerst No doubt! Slippage of the balls must cause a large energy dissipation!
Nevertheless, take a look at this generator, it uses an Toroidal Continuously Variable Transmission, that is a slight variation of this one. And this video shows how it works in a high torque environment:
youtube.com/watch?v=4C3j7LG0S98
arielvollmann 7 months ago
這款CVT一定比一般CVT效率好但是 圖示中的球 應該死得很快
a88629228 8 months ago
DoesB NuVincy know about this development
youtube.com/watch?v=hgl7IBmUj8o
mjdurack 8 months ago
Wow, the simplicity is beautifully powerful!
GnomenKlayture 9 months ago 3
Not even considering the slippage issue, what's the range on this thing from low to high? From the demo it appears that the range would very limited and if that's the case why would I want this on my bike...unless I live where there is nothing but flat land all arould and in that case I would need only one gear anyway.
nourbutwatmi 10 months ago 2
CAN THIS GO FROM ZERO TORQUE TRANMISSION ???
makinamati 10 months ago
@makinamati yes it can
cannibalcorpse360 7 months ago
@cannibalcorpse360 2THANKS!
makinamati 7 months ago
DaVinci vs NuVinci .....sounds copy and paste !
oxoElizaoxo 10 months ago
A bicycle is efficient thanks to it's simplicity, lightweight, no need for additional substances, and totally dependent on your own legs . If you start adding balls and oil to that, you lose the meaning of using a bicycle.
ermalkoci 10 months ago
@ermalkoci Wait... seriously? You never wash your bike, you never clean/oil your chain, never grease your bb? Or, if you don't, those guys racing accross Europe aren't using bikes, but something so convoluted with external BB's, carbon fiber (with the included carbon paste for contact surfaces) fancy gearings, and such? Ok. Go back to your single speed and enjoy being on your soap box.
basftbll35 10 months ago
What is the efficiency of such a mechanism? I see different angle contacts and oil in the system...
Trikoupis 10 months ago
@FranktheBBB ye I see a BIG problem with this, although i have not used this, I would image it has a fair amount of slipping going on, meaning torque transfer is dramatically reduced, which is not good enough for pedaling up hills or using low gears. Is this what you experienced? I wonder how they will attack this problem,
gobacktorussia 10 months ago
So i could have a slipping clutch on my bike ?
35uno 11 months ago
How it react in very low temp. ?
gs400s 11 months ago
gay
picaticatara 11 months ago
where's the motor man?
chippprrr 1 year ago
This has been flagged as spam show
Yes, I ride a busettii Big 50 Mile Bike ! I have had it for 3 months and it is great. My friends have other e-bikes but they are way slower and wimpier than my Busettii. I can get up to 60 miles on one charge and the top speed is about 27 MPH but they are selling at just $1700 now. BECAUSE OF THE BIKE paths and the right shoulder of the road I can go faster than cars across town. I want to try Busettii's new VORTEX mountain bike soon ! It goes 85 miles on one charge. ciao
lovenewtech 1 year ago
Please can between ratios of what and what?
MavisCranfield 1 year ago
When will there ever be a human power vehicle that will achieve 70 MPH?
I want a bike to be like that!
SamuraiClinton 1 year ago
@SamuraiClinton The fastest human powered vehicle goes over 80mph, it was driven by Sam Whittingham. Combination of recumbent bike, streamlined fairing, and LEGS OF STEEL, all made it possible.
teagc 1 year ago
@teagc people have gone faster they had drag assistance tho. Bruce Bursford 208mph
wcline06 10 months ago
Too many small parts. When it breaks, repari would be a bitch!
McWaters12 1 year ago
my rotating balls transfer torque also
RedUnbannable 1 year ago 65
@RedUnbannable that's a theory, You need put Your balls into transmission to prove it.
alexeypetrushin 10 months ago 51
@RedUnbannable
nice for you... your parents must be proud... and btw nite telling your special ability here at this video...
you favorite troll
PAPADRED 3 months ago
absolute genius
sisseeboy 1 year ago
this might work on a bike, but i cant see it handling enough power for a car
pepene93 1 year ago
great!
thaivucom 1 year ago
so the fluid is like a non-Newtonian fluid? Behaves like a liquid, but solid under pressure/at impact?
foxtrotHQ 1 year ago
@foxtrotHQ Like the "silly-putty" I remember from the science museum.. Pliable like putty if kneaded slowly, but would shatter with sudden impact, then return to being pliable.
darkanstormy 1 year ago
@darkanstormy non newtonian fluid. you can make one with corn starch and water. the kids love that stuff
sisseeboy 1 year ago
how much does it costs for a 15-20kW drive?
marcheseDS 1 year ago
cool idea
synesthesia67 1 year ago
If you dissolve corn starch in water to a very thick consistency the fluid is liquid when no pressure or immediate force is applied to it . When you apply immediate force it turns solid ! You can make it in 2 minutes. It is a very unique property. It is similar to the lubricant in this cvt
TheSolarmike 1 year ago
na, what you do is get a unicycle...no need for transmission type hubs lol XD
666TECHNO666 1 year ago
give me the good old chain and sprocket no energy losses this trany like a torque converter in an automatic car transmition has to much losses.for people power
GLOCKIOMM 1 year ago
@GLOCKIOMM there is actually plenty of energy loss in a chain and sprocket system, with all the hundreds of tiny "bearings" between the links, and the bearings that the axles have to ride on, this design by itself will definitely increase efficiency in almost any system it is properly applied to.
meandmyevo 1 year ago
@meandmyevo so you plan on driving the input shaft with?? this is a replacement for the gears, not the chain...
MrMeanderthal 1 year ago
@MrMeanderthal That is a very good point. Apparently I wasn't really thinking much when I posted that. I was actually considering this for small-engine applications (chainsaws, go-karts, scooters, etc)
meandmyevo 1 year ago
@meandmyevo there is larger versions of this device that will handle larger power input.. not sure how big they get but something in the range of 5 hp is already available..
MrMeanderthal 1 year ago
@MrMeanderthal the design doesn't really limit power, just torque. if you had an engine that produced 15lb-ft of torque at 30,000+ rpm, that some seriously usable power that almost any tiny tranny could handle.
meandmyevo 1 year ago
Actually, according to the exhaustively researched book Bicycling Science, and also the 1896 Bicycles & Tricycles: A Classic Treatise on Their Design and Construction, there isn't "plenty of energy loss". The chain-and-gear drivetrain has an efficiency of up to 98%. Nothing comes close to that.
And please, people, there are no "sprokets" on a bike. They're called gears, in general; "chainrings", up front, and "freewheel", "cassette", or "gear" (for you fixie fans), in the back.
craigjacks 1 year ago
@craigjacks
The chains and sprockets are only 98% efficient with all new gear in a laboratory with super lubricants...
Take the same bike down 200 or 300 Km of gritty dirt roads and that soon drops below 90%...
And Mr Pedant - the bikes run sprockets.... all sprockets and nothing but the sprockets.
So get your ungay fakts right.
callmeshane303 5 months ago
How did they get Dug from "Up" to do the commentary?
1cor731 1 year ago
Looks it's not durable. Corrosion will eat it alive. NOT GOOD for harsh conditions
vladokvk 1 year ago
This is actually a terrific idea! However, this should definately be used in vehicles, whose automatic transmissions suffer from significant losses in friction. Meanwhile, bicycle chains are VERY efficient, will rule all high-performance bicycles for decades to come.
swamper777 1 year ago
@swamper777 There are CVT transmissions in some cars. A friend of mine had one and he said it drank the gas because CVT transmissions are very inefficient.
key0bb 1 year ago
He said CVP at the end i think (2:48) - Am i missing something?
And also, I imagine this would let the pedel move if you were resting your weight on it while waiting to go at the lights - unless it has some kind of centrpetal-force-activated gear lock for when your not moving
Also, I would prefer a CVT that automatically increased its gear ratio with increased centrifugal force - which I think was the original design goal of CVTs (Am i wrong?) +Compensation for your prefered cadence
williambrodie 1 year ago
@williambrodie excellent point
mrlew09 11 months ago
CVT are old school. Even with the dilatant fluid, I would of expect more friction than internal hub gear, unless the chemist have recently synthesize a ultra thin & thick viscosity liquid.
I will be impressed if such variable gear in a meshing gear format were possible.
Guesswhokk 1 year ago
@Guesswhokk
Also it probably the heaviest hub out there since all that liquid and large balls of steel were filled inside the entire hub.
All I see with this thing is alot of balls going circle!
Guesswhokk 1 year ago
@Guesswhokk It might even be possible to achieve this with ferrofluids. By using magnets you could vary the viscosity within the casing just as a STF would, and for torque you want resistance. Still, I think STFs would work just fine, you could get constant torque by compressing the chamber at low revs and higher torque naturally at high revs, for cruising open up the chamber even more at high revs for minimal resistance. This CVT is basically a variable torque converter.
dragonamt 1 year ago
Please watch:
THE WORLD'S SIMPLEST TRANSMISSION for BICYCLE
TABAGfrancis 1 year ago
@dragonamt The contact fluids used in here are already EXTREMELY difficult to formulate. I cannot imagine(if it's even possible) how complicated and temperamental a fluid with both of those characteristics would be to produce...
meandmyevo 1 year ago
@meandmyevo Already common in limited slip differentials on cars such as Subaru 4WD models. Silicone based.
GRAHAMAUS 1 year ago
@GRAHAMAUS So... of all the hundreds of Subaru's I've torn into, I have never seen a solidifying traction fluid, nor have I seen a fluid that responds to magnetism in any way. What LSDs on which Subaru vehicles are you talking about?
meandmyevo 1 year ago
THE BALLS ARE INERT!!!
maikeru01 1 year ago
I heard it has high losses but it would still be good for mountain biking since derailers always break
ronmann606 1 year ago
another copy of nissan xtroid...
seanwfd 1 year ago
@seanwfd Not a copy. Similar in nature though. "power rollers" vs ball bearings. And the way they interact also seems a bit different between the 2.
flatblackstrat 1 year ago
@flatblackstrat
cool, then i can get a patent for my crappy CVT idea then. i will make a vid and upload sometime.
seanwfd 1 year ago
I don't know about anybody but I understood almost everything except when the narrator said 2:00 "As you can see... there is a microscopic space" blah blah - fluid being solidified. I think this is a Hydrostatic design but the video sucks at explaining that portion of the fluid mechanics.
aeopmusic 1 year ago
wigser
KINGxa1M 1 year ago
what is the transmision ratio .... not so wide i think...these thing have much smaller range of transmision ratios than the regular shifter...
0Zerooverload0 1 year ago
that's cool, but not for me
rtsoccerplayer 1 year ago
It's a unique design. I would not go as far as saying that it has ratios as in a 12 speed mountain bike sense. Since the balls or spheres are all the same size, the ratios are determended by the amount of viscosity contact pressure between the hubs via the spheres. Low gear would have the spheres further away from the output hub, therefore the fluid would slip more easily through the micro-gap.
It is efficient and works well on a small potable generator. So far.
cobalt120 1 year ago
@cobalt120: The balls engage the rings at different "latitudes" on each side depending on their position/inclination; at one extreme one ring will contact close to the "pole" and the other close to the "equator", thus showing different radii to both rings; thus, the ratio would be something like R(left half) / R(right half). The total variation between the highest and lower "gear" would be (Rmax/Rmin)^2, which depends. on how much you can tilt the balls.
arielco 1 year ago
it looks espencive.
i dont wanna pay 1000 euros for
a bike
cibaca1 1 year ago
Amasing unit there, I'm interested in the design. :)
Maikerunobidio 1 year ago
Do you want to know THE WORLD'S SIMPLEST TRANSMISSION for Bicycle?
Watch: UNIQUE BIKE CRANK ( 2- SPEED)
died4hislove 1 year ago
Do you want to see THE WORLD'S SIMPLEST TRANSMISSION for Bicycle?
Watch: UNIQUE BIKE CRANK ( 2- SPEED)
died4hislove 1 year ago
hutzbe to even call it similar to davinci, what moron put up this name...
carbonhealth 1 year ago
i love this hub
mijdtr 1 year ago
the only question i have is how fast will this allow you to go
fordtaurus1996 1 year ago
@fordtaurus1996 the real question is, how much does that thing weigh!
animalnt 1 year ago
thats cool and makes perfect sense. whoever came up with that is awesome
KrazyKuul111 2 years ago
leonardo da vinci? :D
clustro 1 year ago
briliant
Alanf15 2 years ago
aurgh... the slip... and the fluid resistance.
Ruins the efficiency.
The wear on the smallish ball bearings both lateral and axial will require regular service considering how much they will rotate.
and leaks... dreaded leaks.
Cool thinking though.
Paxmax 2 years ago
I have to agree - as an engineer i think this will be horribly inefficient. And yes the reliability i see as another issue.
sevish885 2 years ago
It does not seem *horribly* inefficient, and I have seen at least two long term reviews in this thing. One using it with lower gearing than advised by the manufacturer, and pushing 2 kids for more than 10.000km in the space of 1.5 years. No maintence, and the hub aparently feels as new.
It was definitly over enginereed, to suport up to 5kw of potency.
Caroliano 1 year ago
@Paxmax leaks can be dealt with, but the wear... yeah... i was just thinking - what are these spheres made of, and how often do they need to be scrapped?
PRIMEx420 2 years ago
Oh, there is practically no wear on the spheres.
It's a gap between spheres and hub wall.
The torque is transfered via a fluid that changes viscosity(hardens) under stress of being forced between hub and sphere.
I think the problem is the dozens of brearings that holds the spheres.
The spheres will exert both axial and lateral pressure + the fluid must NOT leak into bearings or they will practically seize up (the fluids viscosity under stress ya know).
Paxmax 2 years ago
i'm sorry, but... unless i'm missing something fundamental here, that doesn't make much sense... if the fluid can transfer torque, it does so via exerting pressure on the working surfaces... in other words - if it becomes hard enough to transfer torque, it's hard enough to cause wear... just because we're dealing with fluid, doesn't mean wear is eliminated... hydraulic system components wear out all the time, right?
PRIMEx420 2 years ago
Sure hydraulic components wear out. But it is 99% of the times the seals onto moving surfaces.
The hoses doesn't 'wear' out from the liquid inside rushing by, they usually dry out or wear out in joints due to material fatigue induced by pressure shocks.
As long as the solid spheres doesn't touch the solid hug the wear is entirely negligible.
However adding a contaminant of a solid material like sand or hard metal will increase the wearing by a VERY large factor.
Paxmax 2 years ago
i guess you're probably right about the hydraulic thing, however that may have been a weak analogy on my part... in a hydraulic system there is no direct torque transfer... i mean it's not actually relying on traction between two solid components, like this variable transmission does. i mean... it planely says - the liquid momentarily becomes a solid... solids rubbing against eachother? i just don't see a way for this to be frictionless (or have a low enough amount of friction). traction = wear?
PRIMEx420 2 years ago
Well, it never turns into an actual solid, just a high viscosity. If it would turn solid it would JAM the mechanism as soon as it gets moving.
I'm guessing the effect is like corn starch and water. If you add enough corn starch to water you can walk on it as long as you keep moving. If stop you'll start to sink.
As for wear, you can eat your way through a thin sheet of steel with erasers, but it will take 100's of thousands of hours to do it.
With gravel pebbles it might just take you an hour.
Paxmax 2 years ago
well ok, again... to whatever degree it solidifies, that's the degree to which it's effective as a transmittant, and that's the degree to which it's going to cause traction/friction/wear... btw, i'm not 100% on this, that's just what seems logical, and i'm only pushing the issue because i want to understand it. and going with your eraser analogy - motorize the eraser, and trap the particles at the grinding point within a high-tolerance mechanism, and i think you'll have problems very soon.
PRIMEx420 2 years ago
@PRIMEx420
I mean this in the nicest of ways, but if you're going to infer that there's wear, then you're inferring it's a real word system. Of course it's going to wear, everything does. If it was JUST metal on metal, it'd wear out QUIET fast in comparison.
epluribusunum0 1 year ago 4
I mean this in the nicest way, but if you're going to be unnecessarily verbose, at least proof-read before posting, so you don't come off as some half-literate windbag trying to sound impressive while pointing out the obvious. Also, I'm not inferring anything. This isn't the right situation in which to use the phrase "If you're going to infer..." If you think back to the coffeeshop/party/tvshow where you heard someone say that, you'll see that that situation was QUITE different from this one.
PRIMEx420 1 year ago
@PRIMEx420
Hmm. Okay. No offense taken. Insinuating I THINK was the word I was looking for. Oh well. No harm, no foul, and we both know what each other meant and, as far as I can tell, learned just a tiny bit.
epluribusunum0 1 year ago
There was oil leaks problems with the first bacthes, but the manufacturer seems to have replaced the problematic units, and in the new ones don't seem to have this problem anymore.
Also, it is impossible to service it. It is sealed for life with an guarantee of 6 years (and from reviews it seems that it will last an lifetime for regular use)
Caroliano 1 year ago
Suena como una transmicion de carros!!
Porque no usar una en veszde pelotas un disco que jire y que se mueva a los lados , haci da la reverza y la primera o segunda o tercera segun los giros? Con un buen lubricante.
richymss2 2 years ago
genius!
allanseeder 2 years ago
i tried it with my balls it hurt
JOCKATEO 2 years ago 2
@JOCKATEO pffft... ball hurt... walk it off, faggot!
:P
PRIMEx420 2 years ago
I'm curious about it weight, durability, ease of servicing the hub, and how efficient the power transfer is (how much energy is lost in the hub)
Tektribe808 2 years ago
It is quite easy to find this information.. Anyway, the weigth is ~4KG (competing hub gears are 1~2kg); it seems to be ultra-durable, even puting 1kw of eletric power in it; it is impossible to service, sealed for life with an 6 year guarantee; the manufacturer will not disclose the efficiency, but at the same time it don't seems to be too low. Probably at the low's 80%s. That may be compensated by your legs/motor working always at it's peak eficiency, so not that of a big deal.
Caroliano 1 year ago
This is what I am finding!
superpaco1 2 years ago
This comment has received too many negative votes show
Thanks for complicating an already mixed up world. That looks like an utter monstrosity. Can't wait to see them all broken down.
Hoobencan 2 years ago
The shifting of the ball acts like the different size gears... dunno why you don't get the rest, it's simple to me. I just see alot of issues with leaking, and weight. but then I guess the balls could be hollow. although I see the application on heavier vehicles, it seems like alot of device to replace the simplicity of the common gear system on bikes. but I guess its a novelty some might just have to have...
m0okasaur 2 years ago
Not a novelty, for bikes, but the problem is weight. See to ride a bike at maximum efficiency you should ideally pedal at a set speed and decrease or increase your moving speed by changing gear. EG spin your pedals at 1.5 times per second and change gear to change bike speed. This is the most efficient way to ride a bike and racing cyclists would love it. The downside is that if the thing weighs 4 kg it is too heavy for a bicycle.
KrunchyJD 1 year ago
how much
AxSxKxONE 2 years ago
this is sick i want one
jjswimmer2014 2 years ago
could it handle if you make it to cars
over 1000 torque what would it do i wonder
motorsss 2 years ago
This is such an awesome bike. I have one. You have to get one to understand such a difference it makes
pkusingutue 2 years ago
I want one!
mcmt1139 2 years ago
i don't undestand how it works.
can you?
livium10 2 years ago
The circumference of each ball is biggest at the center and smaller near the ends. So, turning the balls at the same point from the center is a 1:1 ratio. As you move towards either end, then one end is spinning closer to the center (a greater distance) and one is spinning closer to the end (a smaller distance). This causes one end to spin slower (or faster) than the other end, giving various gearing ratios.
Brettcomedyzone 2 years ago
no gears, just two smooth surfaces contacting through the liquid. So what % of energy will be lost in that sliiiiide?
Yottskry 2 years ago
its a load of bolls
and it has more flors in it than a multy story car park lol good thinking tho
superbran2008 2 years ago
So if there is a fluid leak at all, the transmission would go slack and be rendered useless, correct? Is there a backup for failure?
Baziachi 2 years ago
probably not. Then again, if a regular gearbox develops a leak and you don't notice it in time, you'll need to call a towtruck as well (or in case of a motorbike : push it home).
XSaenen 2 years ago
I wonder if this would work on a motor cycle
slydewinder 2 years ago
why not if you can make it for bike so make it bigger or larger ?? so it can will be fit to a Mbike
nicolaiholst 2 years ago
mmmmmmmmmmmmmmmmm
tauruxx020 2 years ago
Its Like A Modern VerVariomatic
TheOrangeTurtle 2 years ago
this is great
atomichurley 2 years ago
thats fucking awesome,, damn i love innovation
wellsinmud 2 years ago
may i construct this machine?
ovelho1 2 years ago
as long as you don't sell it, your ok
zantrua 2 years ago
nice idea, the basic design is simple in mechanical terms, but unless the internal parts are made from very strudy components, it would wear out very quickly!
andythedarkone1982 2 years ago
wouldnt you have to keep calabrating it to keep the balls from slipping?
phreezerburne 2 years ago
@500group: boy, am I glad I didn't know this thing couldn't work before I went out for an hour long ride today on my spanking new Crescent Nuvinci. I'm no expert, but there was not the slightest sign of the extra friction you guys claim. No slipping. I never noticed the weight either (but now you said it's so heavy, I'll think about it all the time). For all others, rest assured, it works. The "high friction" if it's there at all, is much too small to be noticed even by my lazy legs.
mwehlou 2 years ago
Sounds like most of the friction is coming from the folks here? LOL
JaleelJohanson62 2 years ago 12
additionally deraillers change gears under constant load, ie your pedalling up hill and you dont have to back off to go to a lower gear VERY IMPORTANT
deraillers chaind and gears with their service requirements and complications are by far still the best soloution
500group 2 years ago
to recap basic physics:
balls, cones, toothless belts, variators, cvt's. all have HIGH FRICTION and are no good for pedal power
chains or toothed belts, gears and deraillers all have LOW FRICTION and are great for pedal power
500group 2 years ago
the bottom line is its just physics, the nu-vinci will always require more pedalling effort and that is a big deal for certain conditions, for a trip around the corner not a problem for a long ride big problem
so the nu vinvi may find an application for casual biking over a short distance
it may be more reliable who know although the plates need constant pressure on them and may be prone to slippage up hills etc certainly deraillers are horrible when it comes to reliability also
500group 2 years ago
the problem here is friction not belts chains balls or anything else.
a chain and derailler allows the least friction, the nu vinci generates substantial friction relative to a chain and derailler (or a toothed belt and derailler for that matter)
500group 2 years ago
oh come on, why invent a wheel all over again?
we have the VARIATOR already, variators can also be made manually controllable, so only really new idea in this nuvincy cvt is that its planetary and probably a little more compact..
martseger 2 years ago
There talking about a bicycle.
The very first question I have, is what is the efficiency?
A good and well maintained drive train on a bike is 98% efficient. If this isn't about 95% efficient, nobody will use it except walmart.
fuzzywzhe 2 years ago 4
This is seems functional, i just wish they figured out some kind of spinning weight system to figure out how hard your pedaling and smoothly shift its self so no need of extra levers or anything on the bike. If shifting was automatic and always required similar pedal pressure every bmx rider would use one of these if the weight was reasonable.
mmcgartland 2 years ago
the on;y down side to this hub is weight
bottlecap33 2 years ago
This hub is heavier but you lose:
- 2 chainrings (plus some linking parts in the crankset);
- the cassette sprockets (358g for Deore);
- the front derailleur (167g);
- the rear derailleur (316g);
- one of the shifters (and the associated cable).
You have a lighter crankset (with just a chainring), a sprocket and a chain between them, no derailleurs, no chain slap.
cgeorgescu 2 years ago
The Alfine is 8 gears inthe hub and weights half what this one does. No doupt though given the money to buy one i would have it on my bike as well.
bottlecap33 2 years ago
Nice, This is a good idea, give it a few years to work out all the bugs. then it will be in alot of stuff. But it still it is not fuel efficient. like the auto trans compared to a stick. the hydraulic aspect is good for comfort but not efficiency.
cillabee1 2 years ago 2
Currently CVT transmissions are the MOST fuel efficient transmissions made for over the road vehicles. It allows the vehicle to select the best drive ratio for a given circumstance. This transmissions along with lock up torque converters are much more efficient than both manual trans and traditional automatics. CVT transmissions are standard on most new Nissan, Saturn, and most of the hybrid vehicles on the road and probably many more.
paintball4life280 2 years ago
my nissan murano with a cvt gets 15mpg
z08north 2 years ago
It's a heavy, powerful vehicle z08. With a 6 speed, it'd get 13-14 mpg!
MrCovertcat 2 years ago
this is a friction drive and therefore no good for bicycles as it will rquire more pedalling power as some of that power has to be used to force the ball against the plate that is no good ! chains are way more efficient
500group 2 years ago
wtf dude? transmitions are the most fable system in a bike....if you were a real life freerider you would have known that...
doldei 2 years ago
Comment removed
mikebike0102 2 years ago
This has been flagged as spam show
Yes.
Lower efficency, higher weight (4.2 kg!), and less gear ratio compared to a chain gear (derailleur).
But probably less maintenace?
I'm not putting one on any of my 10 bikes!
mikebike0102 2 years ago
it might be good for cars or small engine vehicles like scooters. but i think ur right it will not be good for bikes as there will be some slipping likely and powerloss.
MatsNorway 2 years ago
Then why do many motorcycles use belts? Why is the new Soho using a belt? Chains are not better then belts,, they are, at this point, equal. Buy while chains have maxed out there potential we are still seeing improvements in belts. Same with this thing...yes it weighs a fair bit but technology can work out a lot of that, and the other flaws. The ease factor, and the infinite gear possibilities make up for it...at least for me.
NoirMusic 2 years ago 2
MY GOD I LOVE TECHNOLOGY
joesfph 2 years ago