CVT’s or Continuously Variable Transmissions are one of the most misunderstood transmissions in the global automotive market. CVT’s are not inherently a very new idea as it’s origins can be traced way back to the 16th century when the Italian genius, Leonardo Da Vinci conceptualized a vague idea of this revolutionary technology. However, like many of his conceptualized technology, the CVT was also lost in time.
Where are CVT used?
Continuously Variable Transmissions have long been a standard go-to for many applications in the form of lawnmowers, snowmobiles, power tools and a wide range of other daily and industrial tools. These might be the reasons why CVTs have a hard task of conquering an image barrier, an infamous image that has been created due to a lack of proper understanding as to how this transmission works. The CVT technology in its concept is quite an ingenious idea that does come of as a “Why didn’t I think of that?” kind of thought. If we were to look at a lot of cars available for sale right now in the automobile market, we would observe that many vehicles tend to be offered with automatic transmissions that range up to 8, 9 or even 10 speeds. This is just an act to be able to have as many gear ratios as possible to be able to optimize the best power and efficiency at any given point of a ride. How is the CVT different from an Automatic Transmission gearbox, you ask? Well, to put it simply, it gets rid of the traditional “gears” as we know it and offers infinite gear ratios. Sound like something that should just be the answer right? Well, it kinda is, well sort of.
How does a CVT function?
Okay, so diving deep into the concept, the Continuously Variable Transmission works on the idea of completely eliminating the traditional gears that are present in transmission and replacing it with “steps” between low and high-speed operation. Two variable diameter cone-shaped pulleys are connected by a rubber or steel composite belt which is the simplest breakdown of this transmission. The input and output pulleys are capable of varying their diameter on the fly which is actuated by a hydraulic cylinder that provides it with the ability to provide the optimum gear ratio and deliver peak power for any given scenario. This operation mechanism results in an extremely smooth and seamless transmission as there is no jerking or halting as no actual gears are being changed while undertaking acceleration or deceleration. The “non-gear” nature of this transmission makes it a viable transmission to improve power range, fuel efficiency and overall reduce inefficient energy loss.
How does CVT differ from other automatic transmission systems?
The CVT is also a much simpler design when compared to traditional torque convertors or dual-clutch automatic transmissions. This is because the former technology has almost 1/10 the moving parts as compared to the much more complex aforementioned automatics. The CVT as of right now has become more and more common in the automotive scene as manufacturers like Audi, Honda, Nissan, Ford, Toyota, Jeep, Subaru, among the most notable, have at least one model that offers a CVT. However, not all of these CVTs are of similar quality. Among all the manufacturers, Honda and Toyota are known to make the best quality CVTs. They are highly reliable and in case they do break down, very easy to repair. The transmissions are also much swifter resulting is a hasslefree drive. On the other hand, their Japanese counterpart Nissan has various issues with their CVTs. They are known to break down in between a ride and the cost of maintenance is also comparatively higher.
Is it efficient?
The Continuously Variable Transmission when put to use, is extremely efficient under load conditions, for example, climbing a hill as it does not have to constantly switch between gears such to maintain the optimum power and efficiency as it can easily vary the gear ratio to something like a 3.5 that would be perfect for the said application. It is scenarios like these that would really make the user appreciate the smoothness and ease of use that is offered by a CVT.
What are the disadvantages of CVT?
It isn’t all fun and games with the CVT though as it does come with its own set of peculiar problems, the biggest one being the “RUBBER BAND EFFECT”. The rubber band effect is the irritating by-product of a more efficient way of transmitting power as if a user floors the throttle on a CVT, the rotations per minute(RPMs) shoot up to the redline and stay there while the car accelerates as there is no actual gear change which would in other transmissions cause the RPMs to drop at every upshift. This results in the car constantly whining at peak RPMs while it is under hard acceleration resulting in an irritating and not very engaging drive.
Another problem of the CVT comes in the form of a design limitation as it is quite a task for the CVT to be able to transmit a high torque output as the CVT by virtue of its engineering is restricted in the amount of torque it can handle as it takes quite a toll on the driving belt and other components. The CVT is also a much less fun transmission to drive enthusiastically as it is tough to modulate the throttle as there is no feeling in the throttle pedal that the driver can use to gauge his driving style as the throttle pedal doesn’t help determine the operating powerband in a CVT.
What’s the final say?
In a bittersweet conclusion then, the CVT has genuinely improved leaps and bounds from what it initially used to be. The current iterations of the CVT are very impressive in many applications as they are perfect for people who want a smooth, comfortable and efficient drive while not having to stress too much about which gear to choose when. Yes, the CVT has it’s own set of drawbacks which would hinder it from being a choice for many but if technology advances at the pace at which it is strutting right now, it isn’t long before the CVT in engineered to overcome all of it’s leftover drawbacks.