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I did not know that those Nissan concept cars had CVT ...

Anyhow, "the economy of a manual with the convenience of an automatic" ... Sorta ... But most any modern geared automatic will also do that, possibly even better. The ZF 8 and 9 speed automatics, and the Mazda Skyactiv 6-speed, and VW DSG, will all roughly match what a decent driver with a manual transmission could do - and will beat poor drivers of manuals (who don't know how to pick shift points). Heck, even the smart's automated-manual will do that.

CVT does not really have an efficiency advantage over the best geared automatics. The reason is that all CVT mechanisms developed thus far have more friction losses than gear-to-gear transmissions have. Basically it comes out being a wash.

Then there's reliability ... Some newer designs have some hope, but history has not been kind. Quite a few manufacturers have tried CVT and given up. But now Honda and Toyota are on board.

BUT ... and it's a big but. As the article suggests, it's the driving experience. And whether the CVT is a good thing depends on what you are doing with it.

I had a 2013 4 cylinder Nissan Altima rental with a CVT that I used for what amounted to be a straight motorway trip with some puttering around at both ends. For doing that, it was fine. 130 km/h cruise at 2000 rpm (the tallest ratio that it will go to). Come to a slight up-grade and it imperceptibly shifts to a lower ratio, the revs smoothly increase going up the hill and come back down cresting the top, pretty much unnoticeable. For use like this ... No problem. And a lot of drivers use their cars just like that.

The problem happens with the slightest bit of enthusiastic driving where you want immediate pick-up. YES, it has a "sport mode" that keeps the revs higher. But it's just not right. I'm used to one of the cues for how fast I am going being engine sound and knowing what gear I am in - certainly not the only cue, but it's one of them - FWIW I have many years of motorcycle roadracing experience - and with a CVT, that's missing.

Telling quote from that article ... "All I know is, out on the racetrack, CVTs are an exercise in frustration, not efficient power delivery. In fact, the more laps I turned in the Juke Nismo and Forester XT, the more unwilling their transmissions where to deliver the correct gear ratio for anything approaching peak horsepower rpm, let alone at the moment I was asking for it (you know, when you transition back to wide-open throttle coming out of a corner, for example). The inability of these CVTs to handle track duty became even more apparent when they began limiting rpm to a lower and lower level down the main straight. Again, I'm assuming this was a sort of "limp mode" designed to save the gearbox from death due to overheating or too high a workload being asked of the belt and pulleys. Whatever the case may be, the end result was a car parked in the paddock instead of being enjoyed on the racetrack with all the manual gearboxed machines."

No thanks.
 

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I hate CVTs as a driver, and there are so many reliability problems with them - both belts snapping and ECU failures, just a nightmare.
 

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I have owned 2 vehicles with CVT transmissions. One was my 2007 Caliber RT AWD and the other was a 2010 Suzuki Kizashi.
The biggest fault IMO with the CVT is that they are dogs off the line. To preserve the longevity of the belt, the computer will not allow full engine power to at least 20 MPH. In other words, punch the CVT off the lone and it feels like you are driving through a vat of thick goo until it hits 20, then you can actually feel the power start to roll on.
Thats great for tranny life but sucks when you are trying to merge or pull out into traffic from a dead stop.
Plus, the transmission in my Kizashi had to be replaced at 3,800 miles. The CVT in the Suzuki and the Caliber were Identical to the ones in the NIssans, the JATCO JF011E. Nissan owns JATCO, which is why NIssan loves CVT's so much. The 6 speed aisin automatic in my Fiat is SOOOOO much better than the CVT's.
 

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Sigh, dogs off the line.....I personally know that I need Road Warrior response when I "peel out" on my way to CVS. Doesn't downshift like it should (if you are in Deathrace 2014). For god's sake it's a domestic car that is designed to work well in the traffic conditions the average joe encounters. In this I think I see a clue. Who really NEEDS a king cab 14 mpg, with a shiny hood ornament that will pull two Clydesdales out of a mud hole on a regular basis? Not many....but we like to IMAGINE that we do and need a vehicle that can do the job. "RAM tough....and now gets 21 mpg country"....really?
Know what's really cool? A vehicle that gets really good gas mileage, is extremely reliable, and has enough get up and go to not get you killed when merging. And one that has lots of gadgets, or options for same. Or if you just want basics, just those.
If you want a high performance car....buy one. Stop bellyaching about regular cars that don't do that. Makes you sound like a frustrated car reviewer.:|
 

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Mercedes used CVTs in the second generation A-Class and first B-Class. They were an utter disaster, so much so that the new generation cars (A, B, CLA, GLA) use a 7 speed DCT instead. Which itself may be a disaster, time will tell!

Typical problems with the CVT were the total failure of the electronic control unit that lives inside the transaxle casing, followed by belts snapping and other intermittent warnings while driving. The dealers for the first several years had nothing to offer for any type of failure other than a new transaxle assembly for $10K. Now, at least, the electronic failure mode is so common as to have given rise to that part being considered serviceable/replaceable at a M-B dealer, for a mere $4000.

My Mercedes B 200 has a 5 speed manual! In Canada, 95% of them don't. Ha!
 

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and these young pups mock us for wanting a simple low-maintenance manual transmission! sure it's a little old-school, but man, does its simplify your life. and really guys, it's not that hard to do!
 

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How about an electric car with a CVT?>:D
Most of the current generation electric cars have a single speed transmission. Manufacturers have gone various ways on this front.

The 2014 Smart ED is geared such that the relatively lower power motor (55KW) provides spirited driving in the city speeds under 70KM/h. Top speed is limited due to the gearing which makes the motor scream (nicely in fact, sounds great to my ears) at the 145KM/h top end.

Whereas the Chevy Spark EV has a far more powerful motor at 105KW. However, the gearing of the single speed transmission is designed to match the motors maximum 5000RPM. Thus, while the Spark has a massive torque advantage over the Smart, the race to 60KM/h is nearly a draw. Some of that is low rolling resistance tires and traction control limitations.

The Spark EV however is the highest efficiency electric car at the moment. It is comfortable 10% more efficient than the Smart ED. Some of this is down to the design choice of a larger but lower rotating motor and longer gear ratio.

The Smart avoids the use of traction control in dry conditions, yet be nearly the same speed in the city as the far more powerful Spark.

The motor in the Spark EV however is easily able to smoke it's tires. A video on youtube where the traction control has been disabled shows just how traction limited this car is.

In even slightly damp conditions, the Smart constantly hits traction control under full power.

Thus, the design choices of motors and their gearing by the manufacturers have led to a variety of solutions. It is not clear that Smart will feel the need to change their strategy to use a smaller but higher revving motor.
 

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Discussion Starter #14
Most of the current generation electric cars have a single speed transmission. Manufacturers have gone various ways on this front.

The 2014 Smart ED is geared such that the relatively lower power motor (55KW) provides spirited driving in the city speeds under 70KM/h. Top speed is limited due to the gearing which makes the motor scream (nicely in fact, sounds great to my ears) at the 145KM/h top end.

Whereas the Chevy Spark EV has a far more powerful motor at 105KW. However, the gearing of the single speed transmission is designed to match the motors maximum 5000RPM. Thus, while the Spark has a massive torque advantage over the Smart, the race to 60KM/h is nearly a draw. Some of that is low rolling resistance tires and traction control limitations.

The Spark EV however is the highest efficiency electric car at the moment. It is comfortable 10% more efficient than the Smart ED. Some of this is down to the design choice of a larger but lower rotating motor and longer gear ratio.

The Smart avoids the use of traction control in dry conditions, yet be nearly the same speed in the city as the far more powerful Spark.

The motor in the Spark EV however is easily able to smoke it's tires. A video on youtube where the traction control has been disabled shows just how traction limited this car is.

In even slightly damp conditions, the Smart constantly hits traction control under full power.

Thus, the design choices of motors and their gearing by the manufacturers have led to a variety of solutions. It is not clear that Smart will feel the need to change their strategy to use a smaller but higher revving motor.
It was an inside joke. More of a location joke, you had to be there.
 

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Sigh, dogs off the line.....I personally know that I need Road Warrior response when I "peel out" on my way to CVS. Doesn't downshift like it should (if you are in Deathrace 2014). For god's sake it's a domestic car that is designed to work well in the traffic conditions the average joe encounters. In this I think I see a clue. Who really NEEDS a king cab 14 mpg, with a shiny hood ornament that will pull two Clydesdales out of a mud hole on a regular basis? Not many....but we like to IMAGINE that we do and need a vehicle that can do the job. "RAM tough....and now gets 21 mpg country"....really?
Know what's really cool? A vehicle that gets really good gas mileage, is extremely reliable, and has enough get up and go to not get you killed when merging. And one that has lots of gadgets, or options for same. Or if you just want basics, just those.
If you want a high performance car....buy one. Stop bellyaching about regular cars that don't do that. Makes you sound like a frustrated car reviewer.:|
Sigh, i think you misunderstand. Have you lived with a CVT? I have, twice.
Just so you know, i am 57 years old (not some hot rodder kid), and i HATE trucks, i think they are ridiculoous as a commuter vehicle. I drive a smart, a Fiat 500, and a Suzuki SX4. I am enough of a hypermiler that i can usually wring 50+ MPG out of my smart, 40+ out of my Fiat, and high 30's out of my SX4. That is how i drive. I am not"bellyaching" about regular cars that don't do burnouts. I was simply pointing out a negative attribute of the CVT. Unless you have lived with the sluggish acceleration, you really do not know. IMO, most DO NOT have enough "get up and go to not get you killed when merging" (as you put it)
 

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From what I understand, newer cars equipped with cvt limit how you drive the vehicle until it gets to the proper operating temperature, then it lets you drive to your liking. So with that it would seem like the reliability issue with cvt should be fixed.
 
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