Blog : Why aren’t all small autos CVT?

Ian Seabrook

Rover 100 available with CVT
Rover 100 available with CVT

Recently, my Rover 2000 went into a garage for some work and I ended up borrowing a Rover 100 CVT as a courtesy car. I’d not had the pleasure of the ‘gearless’ Metro before and I must admit that I was looking forward to it.

Sure, the build quality was shocking – the remote central locking didn’t work on the driver’s door, but still had to be operated to turn the immobiliser off and the interior plastics (especially those door handles) are horrendously cheap. The wood stuck to the dashboard was just laughable – but that was all secondary. What is a CVT like to drive?

Most peculiar is the answer. Having driven DAF Variomatics before, I sort of knew what to expect, but the quiet work of the engine as you ease away, with the noise a continuous monotone save for a hint of transmission whine, leaves you feeling that something just isn’t right. It truly baffles the mind.

At 30mph, the engine is still humming at a very low speed but, with the K-series engine warmed up after a little pootling, I can give it some beans. This is even more peculiar. The revs shoot up – to one of two preset positions depending on how heavily you stamp on the pedal – and speed increases in a most uncanny manner. Sure, it doesn’t feel as quick as banging through the gears, but it is just a seamless progression.

After a fair bit of driving, it becomes second nature. Sure, it’s a bit ragged in stop/go conditions, with the engine trying to drive through the braking effort you’re providing, but the lack of a clutch pedal is a real joy when things get snarled up, which they inevitably do. You learn to moderate your throttle pressure to keep the revs down, allowing the engine to return surprisingly good economy for a small automatic. Cruising at 60mph on fast roads is no issue at all, with the engine still humming away. It’s all rather relaxing and not at all how you expect a small automatic to feel.

It did leave me wondering why CVT transmission didn’t catch on. At one stage, Audi was even fitting it to their larger saloons and just imagine how much better a Smart would be with a gearbox that didn’t have too many ratios and a clumsy automated gear change? Were people just too unwilling to accept a world where there are no gear changes, no change in engine tone and no sensation at all of a change of ratio? Some manufacturers are persevering with CVT – Dodge and Mitsubishi amongst them – but, generally, these systems just aren’t popular.

Why not?

Keith Adams

22 Comments

  1. Let me get this straight. 1)You’re expecting all the electrics to work on an 18-year-old car? I recently hired a European estate car with defective central locking at 7000 miles. 2) That interior trim looked cheap? Dear me. Not like the competition – Citroen AX, anyone? Another recent hire car was Japanese – the fascia seemed to be made of Lego.

  2. Sorry, but I do expect the electrics to work. I own a 14 year old Subaru and everything works a treat – even the electrically operated heater flaps (I’d be happy with a twisty knob really…).

    I’ll concede that a Citroen AX is equally cheap and cramped – especially as I pointed out to my wife when she had hers that no, the AX didn’t come as standard with illuminated footwells – the heater illumination panel had fallen out!

  3. Yes, I do expect all the electrics to work. It all works perfectly well on my equipment-packed Subaru Legacy, so why not a low-mileage Rover 100?

    I’ll concede that the AX has a cheap interior too – especially as my wife’s old AX used to have illuminated footwells after the heater lighting panel fell out! Mind you, you could get a bottle of wine in EACH door pocket…how French!

  4. Hi, Ian,

    I presume you’re talking about the old Smart 450.

    The new one (451) as a much improved Getrag 5-speed gearbox, sometimes still a bit on the slow side when changing up, but something that you’ll get used too.

    I can’t see why CVT would be better.

    I tried a Lancia Y10 with a CVT box some years ago and I don’t have fond memories of it…

  5. Audi’s foray into the CVT world wasn’t that successful.In the US it was offered as an option with the FWD cars. A lot of reported serious problems in the CVT A4.

    The only larger engine vehicle with CVT that seems to work in the Nissan Murano SUV.

  6. Can someone explain something. CVT = two self adusting pulleys and a rubber belt right? So, with that in mind…

    How does reversing work?

  7. i have a nissan primera p12 with cvt and i can honestly say that i dont think i’d rather have any of the alternatives, having driven conventional autos manuals and a honda with i-shift(flappy-paddle job),
    of course there is the “manual” setting if you want to play with the 6 artificial gears- which can be a hoot.

  8. I agree the metro’s interior plasticwork isn’t the most amazing piece of industrial design (It may have been in 1985, but not by 1995) but it’s not the worst I’ve seen. The seats however are lovely (better in the early Rover Metros than the 100, but still nice) and the driving position a million miles better than the Mini/Metro busdriver affair.

    The C/L is a common fault (underspecified motors/solendoids that fail are the issue usually) but your comments regarding pressing the fob then unlocking the car is a tale I can relate to with my 111i (outside bog spec) as it has the standard immobiliser but no central locking fitted. It takes less than a second to flip the alarm off and then open the door.

    I’ve not driven the CVT Metro but have been led to believe that it’s great at keeping the eight valve 1400 K series in the power band and you can hustle it along at a right pace. The failure of CVT gaining major ground in smaller automatics may be down to the Ford/FIAT CTX/Selecta box of the late 80s which had a high rate of failure and apparently wasn’t a fan of reversing up hills.

    • On the other side of the coin, in the motor scooter world, the belt drive CVT is the dominant transmission, almost 100% of such machines , such a CVT is known as a Variator, not just the scooters of engine sizes of 50 to 125cc, but the “big” maxi-scooters too, 300 to 650cc engines I cannot think of an example without a belt drive CVT. I’m thinking of buying a Honda 350 Forza or a Suzuki 400 Burgman, both are simply twist the throttle and go, no gear changing or clutch, open the throttle and the acceleration is rapid, acceleration without interruptions of gear changes . So the belt drive CVT is not dead, it found a niche in another area of transport

  9. In my experience the Rover Metro is the best CVT out there- as Rhyds says it keeps the engine in the power band all the time when acceleration is required. Other CVTs from Ford and Nissan are awful as is the new Mercedes A-class (W169).

    Perhaps these efforts put people off, as well as the constant engine note being less exciting than racing through the gears.

  10. KM-TV :
    Can someone explain something. CVT = two self adusting pulleys and a rubber belt right? So, with that in mind…
    How does reversing work?

    Imagine a metal belt around two Diablos, and the cones of the Diablos moving in and out, therefore giving a smaller or larger diameter for the belt to run on. I think reverse is usually done by an epicyclic gearset between the cones and the wheels. The controls are exactly like a conventional auto- two pedals and a PRND lever, sometimes with manual gearchange control (up/down).

    Re the door not unlocking, base model Metros had an alarm and immobiliser operated by a remote fob, but no central locking, so this is how it is meant to be. With manual door locking, the alarm and immobiliser have a timeout if not set by the fob, so some owners find themselves not being able to start when the car has been left, unless they use the fob again. The system incorporating central locking is much better IMO.

  11. @ExPatBrit
    The Audi CVT is indeed an interesting creature. I toyed with the notion of purchasing one, but instead of a “rubber-band” belt, they use a titanium “chain”. In their version, they use a computer-controlled multi-pack electically-driven clutch to provide the disconnection between the motor and the wheels when stopped with the engine idling.

    To make things appear more ‘familiar’ to drivers, they offered a “tiptronic”-like fixed-ratio simulation mode, where the CVT switches between fixed ratios in steps, in response to the driver’s input from gear-shift paddles or pushing/pulling on the shift lever, just as on a tiptronic/DSG transmission.

    While I eventually decided against the Audi CVT, more recently I did allow myself to become seduced by their dual-clutch ‘DSG’ transmission.

    The DSG has one weakness and that’s a slight nervousness about the ‘creep-forward’ mode at idle. On a slight uphill driveway for example, if you’re trying to just nip up a tight gap to the bumper of another car, it’s very difficult to have the car ‘creep’ in the same “manageable” way that a torque-converter equipped vehicle does. The same characteristic was also present in the “multitronic”; -their version of the CVT.

    Other than that, the lack of a torque converter in the Audi returns wonderful results in terms of fuel-consumption efficiency… How do the Metro and other ‘modern’ cars achieve the ‘stopped-at-idle’ drivetrain disconnection? -If I recall correctly, the old DAF-style ‘Variomatics’ used a centrifugal clutch, rather like a moped… -Am I imagining that?

  12. KM-TV :
    Can someone explain something. CVT = two self adusting pulleys and a rubber belt right? So, with that in mind…
    How does reversing work?

    The usual approach is to switch in an idler gear stage, which reverses the output direction when engaged.

  13. Our Nissan auto cvt is “dead”

    Don’t think that it is the battery; checked the key plastic headed fuses inside the car and under the bonnet with the fuse puller and they are ok.

    There are two or three fuses which don’t seem to have piece of kit to get them out and that won’t come out by hand. Any ideas and what am I looking for if I do get them out.

    Or could the whole thing be the alternator and do I get it towed to a garage?

  14. Can I say, having tried both, that the ‘old’ AP auto in the VdP 1300 is so much better than a CVT, hot shifting or sit back and relax. If only BMC knew how to soundproof a firewall.

  15. Did British Leyland ever look into developing a CVT automatic transmission, possibly mated to an A-Series or another in-house engine?

    That is apart from Issigonis’s Gearless Mini project or a reputed modified AP Automatic Mini prototype with no torque converter and electronic shift.

  16. I don’t know the answer to your questions, but I can say that the AP transmission was quite delightful , with smooth yet crisp changes, close ratios for an epicyclic box, and a torque converter which never seemed to me to sap power in the way those in the BW boxes did . The 1100 we had was a lovely car to drive, whether in town or on the open road . The DAF which I had was very poor by comparison ( I bought it as a bit of a joke in one of the Fuel crises c.1974 , but the joke was definitely on me), and one of its most irritating habits was to get stuck in a high ratio if one had to stop suddenly because a traffic light changed to red at the last moment – the belts just did not have sufficient time to slide down the cones in those circumstances

    • Might have uncovered a bit more about the updated AP Automatic prototype gearbox used in a Mini.

      Apparently it was a much altered and uprated 5-speed (instead of 4-speed) AP1 Mini Automatic gearbox developed by Keith Gerrard of Bushey Transmissions in conjunction with Jack Knight, which was fitted with a clutch with extra radial shock springs in place of a torque converter and an electronic shift mechanism.

  17. This might need an update as many more cars are now hybrids, almost all of which are automatics.

    Recently I bought a Toyota Yaris hybrid which uses a CVT, which can be a little slow accelerating but is fine once I’m up to speed.

    I bought it because my Wife wanted to take up driving for her job after previously driving an automatic abroad. It was hard to find a small automatic when I was looking, so decided to take the plunge with a hybrid.

    • The hybrid has taken transmission a step further than manual with clutch, or, automatic with torque convertor, the hybrid is adopting the gearless approach, take the latest Jazz, runs on battery power to a traction motor at slow speeds, engine driven generator to battery and traction motor at medium speeds, for higher speeds the petrol engine couples directly to the road wheels, (effectively the car is in top gear)
      the Jazz does not have a transmission, basically a drive direct to the road wheel differential. Owners are reporting very high mpg returns from the Jazz in real world driving conditions, as much as 70mpg

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