CVT does not have seven steps.

[mikebore]

This is a spin off from this thread to avoid hijacking that thread which was about something else altogether.

In that thread Kenneve said:

"Re the CVT issue, as I understand it from other posts read on this forum, the CVT gearbox on the Mk 3 has been programmed to provide 7 steps in the ratios more akin to a conventional auto box, rather than continuously variable like the Mk1/2 boxes.
To my mind, this is a backward step as the previous box was always in the right ratio for the prevailing conditions. Maybe this has been done to placate those motoring journalists who thought the engine was racing unnecessarily during their road tests.
However I did read on a later post, that on a vehicle with a few thousand miles on the clock, this condition had 'worn off'
Please correct me if I've got this wrong".

The CVT is still continuous. However, The introduction of the dual cycle engine, (Atkinson for low power and Otto for high power) has led to some clever stuff going on with the way the CVT works because it now has a different job to do to match the ratios to suit the engine.

Additionally Honda did say in a press release that they have made changes to the CVT to be more like a stepped change. There is a thread about this somewhere with the exact quote. Will see if I can track it down.

So there are certainly grounds for a rumour that the Mk 3 is now 7 step, and IMO it is different from the Mk2, but not as much as saying that it is now 7 step implies.

[John Ratsey]

A few days ago I gently accelerated from 30 mph to 60 mph with the engine staying at 2000 rpm throughout. So which gear was I in?

However, normally the car does make noticeable changes to rpm to reflect changing performance requirements as indicated by the position of the accelerator pedal. One that is noticeable is a jump from around 2000 rpm when cruising at 60 mph (revs proportionally below / above this depending on speed) to around 2800 rpm if there is a need to accelerate. This, I suspect, reflects the engine changing to the Otto cycle mode and there's no point in making the change gradually when the driver probably wants the car to get a move on.

Overall, I'm very happy with the behaviour of the CVT and wouldn't consider it a reason for looking elsewhere. There is evidently some very complex programming which tries to balance performance and ecomomy. For example, sometimes I feel that the car is labouring up a hill so I tug the left paddle to tell it to change down but frequently the car will change up again within about 10 seconds (albeit after speeding up).

I also feel that there is nothing new in the CVT appearing to not be continuous. My previous Jazz (Mk 2 hybrid) definitely had its preferred engine rpm ranges and would jump between them.

[andruec]

The CVT definitely seemed more 'steppy' when I first got it. There's one long average steep hill I drive every weekday (the A422 between Brackley and Steane Park. On Mk1 and Mk2 vehicles it was always possible to just gradually press down on the accelerator to maintain speed (50mph) and the revs would just gradually rise. When I first got my Mk3 it would noticeable change down half way up where it gets a bit steeper. Now it mostly doesn't. Once or twice it has done but it's usually when I've let the speed drop off and have used a bit more accelerator.

Another trick I like with the CVT is to kick the engine to 3,000 rpm then hold it there as I accelerate. That gives brisk acceleration without being excessive. Initially the Mk3 just didn't want to play ball. Either it wouldn't bounce up or else it jumped to 4,000. These days I'm mostly back to how I like it although I think it's down to me learning the trick of it. I think that as John has said the change in engine means that I might be trying to do something that is no longer valid. The Mk1 and Mk2 seemed to have an affinity for 3,000 and that may simply not be the case with the new engine.

So what I'd now say is that after you've driven 4,000 miles the CVT shouldn't operate much differently than in earlier models most of the time.

However there is one niggle I still experience. Occasionally - often when pulling away from a roundabout - my Jazz doesn't seem to want to accelerate. I haven't yet worked out if it's something to do with the accelerator pedal (my shoes often seem to be touching the edge of the pedal well) or the engine. Or even maybe some kind of traction control.

[mikebore]

Additionally Honda did say in a press release that they have made changes to the CVT to be more like a stepped change. There is a thread about this somewhere with the exact quote. Will see if I can track it down.

Here is the full text about the CVT from the Honda Press release I mentioned above.

Easy to understand why some think it is now seven step !

"For the 2015 Jazz, Honda’s popular, optional CVT is a newly-developed unit delivering better fuel economy and significant improvements to driveability. An all-new CVT control logic was developed specifically for European markets to deliver the direct and linear feeling expected of a manual transmission. This results in vehicle speed matching accelerator pedal position more closely for a more direct feel, while engine speed increases proportionately to accelerator pedal position for a more linear feel.
The CVT’s driveability is given a more natural ‘multi-gear’ feel through the use of new control software exclusive to Europe which simulates seven speeds and provides optimised gear change mapping. Two new additional programmes provide situation- specific enhancements.
Early Downshift During Braking (EDDB) utilises the engine to assist the driver during braking. When the system recognises a deceleration, downhill, or cornering situation initiated by the braking system, EDDB automatically increases the engine speed to provide engine braking. This then allows for quick re-acceleration after slowing or quick acceleration after cornering.
Fast Off measures how quickly the driver releases the accelerator pedal and maintains engine revs to provide engine braking in situations where the driver has released the pedal quickly. This system has been extensively tested for Europe’s high speed, multi- lane roads. For example, Fast Off recognises when the driver has prepared to pass a vehicle in front, but is unable to complete the manoeuvre due to a vehicle in the next lane. As the driver quickly releases the accelerator pedal to let the vehicle behind pass by, Fast Off maintains a high engine speed in preparation for completing the overtaking manoeuvre.
This newly-developed CVT unit delivers impressive fuel economy in conjuction with these significant improvements to driveability. The CVT gearbox allows the engine to operate within its most efficient range more of the time by continuously varying the gear ratio instead of adjusting the engine throttle opening. Automatically managed by the engine management system, the CVT gearbox selects the optimal ratio within the simulated seven speeds depending on engine speed, throttle position and driver input. Economy is boosted further by the transmission’s wider ratio range and reduced
weight, the result of a rationalised design with reduced pulley pressure. Reductions in friction have been achieved through an optimised oil pump capacity, reduced oil resistance, a low friction reverse brake and a reduced friction from the rotational sliding parts.
Equipped with the CVT transmission, the 2015 Jazz accelerates to 100 km/h (62 mph) in 12 seconds, and achieves a top speed of 183 km/h (113 mph)".

[VicW]

The 7speed function is not new to the Jazz as the GD/MK1 CVT had it, as a pointless, driver selected option.  Why have a seamless CVT system and then fit it with an artificial stepped function?

On the reintroduction of the CVT in the facelifted 2011 Jazz Mk2 the 7speed option was left out although the manual paddles were retained.

Vic.

[andruec]

The 7speed function is not new to the Jazz as the GD/MK1 CVT had it, as a pointless, driver selected option.  Why have a seamless CVT system and then fit it with an artificial stepped function?

But we're not talking about that. Or at least I'm not. I'm talking about the tendency for the Mk3 CVT to make step changes when operating in default mode where the previous models didn't. The only time I ever remember the Mk1 or Mk2 CVT making a step change in normal mode was when I triggered a kick down.

It is a lot better than when I first got it and most of the time it's seamless but it's still not as good. With the Mk1 and Mk2 I was happy to leave the CVT to do it's thing because you could almost forget it's even there. But with the Mk3 I'm always mindful of what it's doing and to me that detracts from its beauty. My rev counter is suddenly more important than it used to be. Maybe that's what Honda mean. They have introduced the ability/need to interact more with the vehicle. Whatever the cause I feel it's a shame. I own an automatic because I don't want to have to think about gear changes or engine revs. Mk1 and Mk2 were 'push and go' cars. Mk3 seems to require a bit more thought.

[mikebore]

I think the differences are largely the consequence of having a two mode engine, and so is the price we pay for achieving a combination or performance and economy not matched by the Mk1 or Mk2.

I suspect Honda may be making a virtue out of necessity saying they have deliberately introduced steps to make it more natural etc. Just a feeling.

[Downsizer]

Mk1 and Mk2 were 'push and go' cars. Mk3 seems to require a bit more thought.

  I never drove a Mk 2 cvt, but to me the Mk 3 cvt is "push and go" and doesn't require any thought about revs or gears.  Certainly the revs rise when you want more torque for acceleration or a hill, and then drop back, but no driver action is needed apart from a bit more right foot.

[mikebore]

Mk1 and Mk2 were 'push and go' cars. Mk3 seems to require a bit more thought.

  I never drove a Mk 2 cvt, but to me the Mk 3 cvt is "push and go" and doesn't require any thought about revs or gears.  Certainly the revs rise when you want more torque for acceleration or a hill, and then drop back, but no driver action is needed apart from a bit more right foot.

Agreed. It would be easy for someone without experience of the Mk3 to get a very false impression from this thread.

[edam]

I think the differences are largely the consequence of having a two mode engine, and so is the price we pay for achieving a combination or performance and economy not matched by the Mk1 or Mk2.

I suspect Honda may be making a virtue out of necessity saying they have deliberately introduced steps to make it more natural etc. Just a feeling.

When Im driving in "S" I do notice, no I wont say the "G" word , a sudden reduction in engine revs which makes it feel like a normal auto. If I try to make it happen I never succeed . I thought it may be the air con but it still does it with the air con off.