No they do not break all of the time; snowmobiles use them, like in Alaska where you could be 500-700 miles away from anything. One half of each "pulley" moves and the belt is that so hard to see? not to mention they can be sealed just like every thing else on earth all the sport & utility quads use them example: KFX, Brute force, grizzly, Arctic cats, Polaris's, Hondas's, renegade 500 & 800, outlander, subaru 360, Nissan, hay carts, shifter carts and other things look at "Karting CVT system".
It is the centrifugal force pulling the pulley together in the front which the belt rides up changing the ratio and opposite for the back, the belt gets pulled down to the shaft because the front pulls the slack out of the belt.
yes I get that. I also get the claim that they are positioned by centrifugal wedging. I'm a little puzzled how they can move in such sync with such a crude system but be that as it may.
either way it's not relevant. electric motor with fixed gearing will rule. CVT need not apply
@DanFrederiksen since an electric motor like all motors have an RPM at which they are most efficient, a CVT would be a match made in heaven. A fixed gear that has the proper ratio for the desired top speed would draw too many amps to start rolling from a stop in something like car.
@pattyaaron I understand you might think that but that's not the case. the tesla roadster does 0-100km/h in 4 seconds and top speed of 200 all in a single fixed gear. 1:8.27 iirc
and most cars don't need to be able to go that fast if they have better acceleration performance so you could just span 0-150km/h and it should be easier still.
@DanFrederiksen It really is very simple, from a a dead stop the load is greatest, as is the current draw, much of the energy is wasted as heat in a "stop and go" situation. At "cruising" speed amp draw would be the least.
@pattyaaron it's also very faulty. you're right that current is dominant at low speed but that current to voltage ratio doesn't inherently imply that adding the inefficiencies of a CVT would be better..
you confuse the correct observation that efficiency drops at low rpm with low speed efficiency being very poor. while the efficiency map of an electric motor will droop at low speed it may still be very flat just with a slight curvature at the very edges. insignificant in average use
@pattyaaron I found a PDF that claims these efficiencies (I assume as typical values)
Manual 97%
Automatic 86%
CVT belt 88%
CVT toroidal 93%
and a fixed chain gearing can be 99% efficient.
you might want to think about adding the weight and cost of a CVT system into a bigger electric motor that can handle higher current at higher efficiency. think about it
@DanFrederiksen try an experiment get on a multi speed bicycle and start in top gear, it can be done, right? does that mean the extra complexity of multi speads makes a human powered machine more or less efficient? It is more efficient right?
@pattyaaron hmm your willful stupidity is beginning to bore me.
the human motor system has very different characteristics than a high rpm high efficiency electric motor. unless you admit your mistake I will not answer you again
@DanFrederiksen So If a human powered machine can see benefits from a "transmission" or multi gears, you feel that an electric motored machine would somehow be mad less efficient with the ability to change gear ratios? So human propulsion is superior beacuse it overcomes the "inefficiencies" of CVT? Of course not...
get used to a snowmobile clutch and never look back. any chance this going into production? the motorized bicycle crowd would find this thing is a smash-hit. staton-inc should get a look at this. excellent stuff
Yes, they also spin in the reverse-direction. The Dutch "Daf" cars, were the first to ever feature this type of transmission. It's an Dutch invention to, called "variomatic". The Daf's could theoretically go the same speed in both directions. Takes a lot of nerves though.. :D
It was built for the speed car I am building for the speed event in September. I am hoping to get 150mph with 3 engines driving this unit to the rear axle
can anyone ship this to Bali?
sanditra1 4 months ago
Nicely done
1BustedMyth 4 months ago
How do you control the pulley's side movement?
AhmadAboulFarag 6 months ago
What kind of counter weights do you use? Can we see a disassembly of the CVT?
calvinthedestroyer 7 months ago
What changes the belt ratio?
sayrith 8 months ago
Does BMW know about this development
youtube.com/watch?v=hgl7IBmUj8o
mjdurack 9 months ago
nice!
carboncatperformance 9 months ago
How big is this? Can it be purchased? Where?
gregryf 10 months ago
man cvt..... im a beliver :]
NastytheGREASERZOMBI 11 months ago
How did you figure out the right weight to use in the drive and driven clutch? How long did it take to develop this?
bitsurfer0101 1 year ago
What belt do you use in this CVT? Is this an off the shelf belt?
What's the belt length, and distance between axis?
Where could I get more info on this CVT? I'm impressed... congratulations!
JDrwal2 1 year ago
Hi! I'm very interested in CVTs / IVTs for various hobby / design projects, I have the following question:
What causes & controls the change of ratio / movement of the belt?
THANKS!
daManDRAK 1 year ago
@daManDRAK centrifugal force
gregryf 10 months ago
Thats very nice
SuperDisco91 1 year ago
I want one!
ragonamuffin 1 year ago
so smooth dude ... It makes a nice feeling in my pants
SquidgyMcGee 1 year ago
have you built taht yourself?
wwilliam7 2 years ago
Comment removed
shaynebilton 2 years ago
i need something like this - what ratio is this working on?
sneekmatrix 2 years ago
Doubt a CVT would work in an f250 pulling a load for 200k miles. More likely good in light weight / low mileage applications.
sunabich 2 years ago
F1 sound
toshi9761 2 years ago
but how efficient are they and how well do they last? it doesn't look ideal in either department
DanFrederiksen 2 years ago
They are the most efficient in transferring power and have the least maintenances because there are only 3 moving parts.
yamasubaruger 2 years ago
if there is only 3 then how does it change gear? of course it's not that simple and I hear they break all the time.
electric transmission is the way to go
DanFrederiksen 2 years ago
No they do not break all of the time; snowmobiles use them, like in Alaska where you could be 500-700 miles away from anything. One half of each "pulley" moves and the belt is that so hard to see? not to mention they can be sealed just like every thing else on earth all the sport & utility quads use them example: KFX, Brute force, grizzly, Arctic cats, Polaris's, Hondas's, renegade 500 & 800, outlander, subaru 360, Nissan, hay carts, shifter carts and other things look at "Karting CVT system".
yamasubaruger 2 years ago
I see them move but what makes them move?
DanFrederiksen 2 years ago
It is the centrifugal force pulling the pulley together in the front which the belt rides up changing the ratio and opposite for the back, the belt gets pulled down to the shaft because the front pulls the slack out of the belt.
yamasubaruger 2 years ago
how does the centrifugal force turn into contraction?
DanFrederiksen 2 years ago
it,is,internal,springs,and,weights,with,linkages,when,the,weights,get,pulled,outward,the,linkages,pull,the,clutch,halves,closer,together
mageac 2 years ago
Its a set of springloaded rollers on the inside of the pulleys set up in such a way as to push the pulley up or down when they are forced outward.
pillsauve 2 years ago
flyweights.
ratheads 2 years ago
snowmobiles,and,relibility,should,never,be,in,the,same,sentance...
mageac 2 years ago
Sigh.
They don't change gears; that's the point.
pillsauve 2 years ago 9
obviously there are no actual gears. gearing is a generalized term irrespective of the use of actual tooth gears
DanFrederiksen 2 years ago
They change ratio by use of roller-driven spring-loaded centrifugal pulleys. See how they're moving up and down here, changing the ratio?
pillsauve 2 years ago
yes I get that. I also get the claim that they are positioned by centrifugal wedging. I'm a little puzzled how they can move in such sync with such a crude system but be that as it may.
either way it's not relevant. electric motor with fixed gearing will rule. CVT need not apply
DanFrederiksen 2 years ago
@DanFrederiksen since an electric motor like all motors have an RPM at which they are most efficient, a CVT would be a match made in heaven. A fixed gear that has the proper ratio for the desired top speed would draw too many amps to start rolling from a stop in something like car.
pattyaaron 1 year ago
@pattyaaron I understand you might think that but that's not the case. the tesla roadster does 0-100km/h in 4 seconds and top speed of 200 all in a single fixed gear. 1:8.27 iirc
and most cars don't need to be able to go that fast if they have better acceleration performance so you could just span 0-150km/h and it should be easier still.
the motor in a tesla goes to 13000rpm
DanFrederiksen 1 year ago
@DanFrederiksen If the Tesla Roadster had a CVT it would have a longer range, especially in city driving, I guarantee...
pattyaaron 1 year ago
@pattyaaron I very much doubt that but feel free to say how you figure that
DanFrederiksen 1 year ago
@DanFrederiksen It really is very simple, from a a dead stop the load is greatest, as is the current draw, much of the energy is wasted as heat in a "stop and go" situation. At "cruising" speed amp draw would be the least.
pattyaaron 1 year ago
@pattyaaron it's also very faulty. you're right that current is dominant at low speed but that current to voltage ratio doesn't inherently imply that adding the inefficiencies of a CVT would be better..
you confuse the correct observation that efficiency drops at low rpm with low speed efficiency being very poor. while the efficiency map of an electric motor will droop at low speed it may still be very flat just with a slight curvature at the very edges. insignificant in average use
DanFrederiksen 1 year ago
@DanFrederiksen XBOX
360 or PS3?
pattyaaron 1 year ago
@pattyaaron ? I have neither
DanFrederiksen 1 year ago
@DanFrederiksen Heavily loaded or starting from a stop up hill or both, the amp draw would be far more than "insignificant"
The fact of the matter is that a way to change or adjust gear ratios "on the fly" is advantages regardless of gas or electric drive...
pattyaaron 1 year ago
@pattyaaron how big a percentage of the time you drive would that be?
and how big a percentage of the time would it suffer the CVT losses..
DanFrederiksen 1 year ago
@pattyaaron I found a PDF that claims these efficiencies (I assume as typical values)
Manual 97%
Automatic 86%
CVT belt 88%
CVT toroidal 93%
and a fixed chain gearing can be 99% efficient.
you might want to think about adding the weight and cost of a CVT system into a bigger electric motor that can handle higher current at higher efficiency. think about it
DanFrederiksen 1 year ago
@DanFrederiksen toroidal is the key.
pattyaaron 1 year ago
@DanFrederiksen try an experiment get on a multi speed bicycle and start in top gear, it can be done, right? does that mean the extra complexity of multi speads makes a human powered machine more or less efficient? It is more efficient right?
pattyaaron 1 year ago
@pattyaaron hmm your willful stupidity is beginning to bore me.
the human motor system has very different characteristics than a high rpm high efficiency electric motor. unless you admit your mistake I will not answer you again
DanFrederiksen 1 year ago
@DanFrederiksen Funny how the ignorant always turn to insults...
pattyaaron 1 year ago
@DanFrederiksen Dude, grow up.
Ryoukun16 1 year ago
@DanFrederiksen So If a human powered machine can see benefits from a "transmission" or multi gears, you feel that an electric motored machine would somehow be mad less efficient with the ability to change gear ratios? So human propulsion is superior beacuse it overcomes the "inefficiencies" of CVT? Of course not...
Look up the "nuvinci cvt hub"
pattyaaron 1 year ago
@pillsauve ...well... they "do"...
Zoomsterful 8 months ago
@DanFrederiksen The design is excellent. Dependability depends upon the quality of the parts used.
gregryf 10 months ago
Can I put it in my DAF car? ;-)
glasjanus 2 years ago
is it possible to install this on a superkart?
Dimitri0809 3 years ago
This cvt can be improve the performance of a brushless hely?
Where can I find plans to built it?
alex681219 3 years ago
get used to a snowmobile clutch and never look back. any chance this going into production? the motorized bicycle crowd would find this thing is a smash-hit. staton-inc should get a look at this. excellent stuff
devja71 3 years ago
will these type of transmissions work spinning in the reverse direction and can they be made to work with a low rpm?
crawldood 3 years ago
Yes, they also spin in the reverse-direction. The Dutch "Daf" cars, were the first to ever feature this type of transmission. It's an Dutch invention to, called "variomatic". The Daf's could theoretically go the same speed in both directions. Takes a lot of nerves though.. :D
Skoda130 3 years ago 2
how did u make this
danielokuda 3 years ago 10
Smooth engine...sounds like an air gun. ;-)
TimsFlicks 3 years ago 2
This is really wonderfull.perfect..
I want to use this cvt for my rc car.How can I buy this?
serhaal 3 years ago 3
my golf cart runs the same style thing. thats awsome man.
jrodrc1 3 years ago
It was built for the speed car I am building for the speed event in September. I am hoping to get 150mph with 3 engines driving this unit to the rear axle
Cheers
ajlovering12345 4 years ago
What is the rpm at engagement and also when it starts to change ratios.
Weight - is it heavy.
raysrc 4 years ago
It is always engaged and shift at 20 000RPM.
The clutch is design to be used in a RC nitro car.
bigpipo305 4 years ago
Works like a old HONDA ODYSSEY ATV, or snow mobile clutch.
raysrc 4 years ago
Wow! Witch Company built this C.V.T.?
98racingteam 4 years ago