City CVT question..

**Shalooney** · April 29th, 2008 04:34 AM

Hi. Well I don't know much about cars so forgive me for this dumb question. My dad just got a Vios and now we're thinking of buying a City for me and my brother.. Anyway, I don't really understand the terms on Honda's specifications. I only get the Toyota terms. So what is CVT exactly?? There's a 1.3 City that's CVT also, what's that? We want an automatic.. so what is the equivalent of an automatic in the City?
Thanks.

**CVT** · April 29th, 2008 07:34 AM

Originally Posted by Shalooney

Hi. Well I don't know much about cars so forgive me for this dumb question. My dad just got a Vios and now we're thinking of buying a City for me and my brother.. Anyway, I don't really understand the terms on Honda's specifications. I only get the Toyota terms. So what is CVT exactly?? There's a 1.3 City that's CVT also, what's that? We want an automatic.. so what is the equivalent of an automatic in the City?
Thanks.

CVT stands for Continuously Variable Transmission, which means that you have infinite gear ratios (and you do not have discreet gear ratios like a regular A/T). For Jazz and City,- CVT is the equivalent of an Automatic.

Sales personnel normally state this in terms of no shift-shock, unlike the regular A/T, and better fuel rate consumption.

Here's a definition from
http://en.wikipedia.org/wiki/Continu...e_transmission

A continuously variable transmission (CVT) is a transmission which can change steplessly through an infinite number of effective gear ratios between maximum and minimum values. This contrasts with other mechanical transmissions that only allow a few different discrete gear ratios to be selected. The flexibility of a CVT allows the driving shaft to maintain a constant angular velocity over a range of output velocities. This can provide better fuel economy than other transmissions by enabling the engine to run at its most efficient revolutions per minute (RPM) for a range of vehicle speeds.

5909:burn:

**Type 100** · April 29th, 2008 09:04 AM

There are a number of kinds of CVTs, but the ones most commonly used, and fitted to the GD Jazz and City, make use of a thick steel belt and two special pulleys.

One pulley is connected to the engine, the other is connected to the drive wheels (the fronts). The pulleys are special because they can vary their working diameters, getting smaller or bigger depending on the engine load and demands of the driver.

This process of pulleys expanding and contracting gives the effect of gears in a normal transmission. However, since there are technically no gears in a CVT, there is no noticeable "step" in power and the pulleys can vary their diameters continuously (hence the term CVT - continuously variable transmission). This makes for smooth acceleration and better fuel economy.

For the CVT's manual mode, the CVT's computer locks the pulleys into a number of distinct size combinations (for the Jazz and City, 7) to give the impression of manual shifting.

Nissan is also a longtime CVT manufacturer. They've been at it for 20+ years now, even using it for a high-torque application such as the Murano SUV.

**suysuy** · April 29th, 2008 10:07 AM

CVT in not really an automatic but it IS like an automatic. CVT's are very fuel efficient even rivaling that of manual. and for acceleration? also fast. 8seconds 0-100 is very achievable in the jazz/city CVT (1.5 VTEC)

**ghosthunter** · April 29th, 2008 10:30 AM

One limitation of the CVT design is the amount of power it can handle. That is why CVT trannies are found on cars with smaller engine outputs.

**mbeige** · April 29th, 2008 11:37 AM

Only thing I don't like about the CVT is its boring sound. It just feels like it's humming, and that's it. I miss the increase of RPM, shift and RPM drop followed by another cycle of RPM increase, etc. Of course this can't be done with the CVT since the constant thing is the RPM and the gear ratios just change (or vary, in this case).

**suysuy** · April 29th, 2008 12:17 PM

although most manufacturers also put an option to imitate a conventional automatic like the 7 speed mode in honda plus you can control the "gear" hehe

nissan has CVT in their murano and teana in which both have 3.5L V6 engines

**Shalooney** · April 30th, 2008 02:29 PM

Ohh. Okay. Thanks for all your replies.

**Type 100** · April 30th, 2008 07:55 PM

Originally Posted by mbeige

Only thing I don't like about the CVT is its boring sound. It just feels like it's humming, and that's it. I miss the increase of RPM, shift and RPM drop followed by another cycle of RPM increase, etc. Of course this can't be done with the CVT since the constant thing is the RPM and the gear ratios just change (or vary, in this case).

The Americans call this the "motorboat syndrome" of CVTs.

This is most evident when you give the engine full throttle and expect instantaneous acceleration. Instead, the engine gets really, really noisy, but the car's actual speed climbs at a gradual pace as the CVT's brains work out the ratios of the pulleys, gradually lengthening the drive ratio.

Needless to say, CVTs weren't meant for those sorts of drivers. The raison d'etre of CVTs is fuel economy and smoothness.

**mbeige** · May 1st, 2008 06:58 AM

Originally Posted by Type 100

The Americans call this the "motorboat syndrome" of CVTs.

This is most evident when you give the engine full throttle and expect instantaneous acceleration. Instead, the engine gets really, really noisy, but the car's actual speed climbs at a gradual pace as the CVT's brains work out the ratios of the pulleys, gradually lengthening the drive ratio.

Needless to say, CVTs weren't meant for those sorts of drivers. The raison d'etre of CVTs is fuel economy and smoothness.

No wonder

Try to shift into S mode and you'll get better response though! When I want to pass somebody I don't floor it anymore; instead, I slightly jab at the accelerator and simultaneously downshift to S in the CVT. Gives it better response, much more satisfying than the "motorboat syndrome," which actually becomes mind-numbing after a while.