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Interesting find Bomi,.....Sounds logical ,..the need for a large master in an auto box !
Has this been noted in any other Indian car (corolla / accord etc)

putting into l at high speeds will throw out the gear wheels out of your box.never try it because you are putting your vehicle into 1st gear or 2nd gear At high speeds.its always nice to pump brake.
ram

As Ram said, do not ever put into L when doing high speeds. you will cause some serious damage to the gearbox.

I drive NHC MT and I see that the rpm is @3500 at speeds @120kmph...

So if CVT achieves this speed at 2500 RPM, it's a terrific achievement.

Even if I accelrate very sedately, I let's say reach 120kmph and then drive steady for a lot of time, my (MT) rpm stabilises at 3500 rpm...


So at the constant speeds of 100/120 kmph, CVT should give a much much better FE.

Can someone please confirm?

Hi,

> Having driven both the CVT & the MT very reguarly at highway speeds.

At last somebody who can give opinions on both!

> In the CVT you need to learn to modulate the throttle more often than the > MT, as the CVT responds to even the tiniest input and shifts cogs.

I totally agree with you on this. Any more or less pressure on the accelerator can be seen in the RPM meter.

> ;-example in the MT @ 120kmph I am at 3500 rpm~, in the CVT if cruising
> with a light foot you can manage the same speeds even at 2500 rpm~.

I assume the 120kmph@3500rpm in the MT is in the fifth gear. So the gearing is around 300rpm for every 10kph. In the City yahoo groups, another MT user has said it is about 250rpm for every 10kph.

I have confirmed that in my CVT, the best gearing that I can mage is 250rpm for every 10kph ie. a steady 1500rpm at 60kph. Once the speed goes below that it slips into lower gears. And above if I ease off the throttle I can maintain that 250rpm for every 10kph increment.

120kph at 2500rpm would be around 200rpm for every 10kph increment. I should try this.

I have hardly used S and have used L only for long slopes. I have used the 'kickdown' a couple of times to overtake.

Just my thought...pls correct me, if i am wrong.

Is it possible that one of the brake lines in the funkydevil's cvt might be broken/notworking? I think all cars have 2 independent brakelines for redundancy. If one of the brakeline is broken..you can still use brakes but the braking efficiency will be severely effected.

Is this a possibility?

Thanks
-Vasprbo

That is correct anand,..the CVT if I am right is a 7 speed automatic unlike others which are normally 4 - 5 speed boxes. However the higher gears are overdriven meaning are good only for cruising, the moment you press even a millimeter harder it down shifts to lower gears and the rpm climbs.

At a steady crusing speed the CVT gives about the same if not slightly more FE than the MT. I must say this is the best auto box I have driven till date in the Sub 10 lac segment.

well, thanks for all your reply's guys, just for the record my city has no abs.

Now i asked around and even went through some forums n tried to find out. When in 'D' mode the gears change and the car takes time to reach a certain speed, say 100. But in sports mode you dont feel the gears changing as in D mode. I mean i donno how to explain it but, try putting a cvt city in s mode n going from 0-100 u wont feel the gear change at all and the rpm is like always high, very high in fact some where arounnd 5000+. Altough the cvt is a very smooth transmission when in 'D' mode u can feel the gears changing with a very slight jerk, (very slight) this is not so in the 'S' mode. (According to what i have noticed in my cvt and a friends city cvt) In the forums they say that cvt doesnt brake as well as manual because when at high speed when in D mode the car takes time to change into a lower gear hence your effect of braking will increase only when when the rpm needle goes down which i have noticed at times, in high speeds, does take a while even if your foot is off the gas pedal. And yes in sports mode braking is more effective as unlike 'D' the gear change downards is just as fast as the gear change upwards. By the way people in some of the forums, said since CVT is Continious Variable Transmission, the gear ratio's are unlimited as the transmission is variable unlike other automatics. I never got what this meant, n is this the reason braking gets effected due to slow gear change.

just thought this might be of interest

Howstuffworks "Transmission Basics"

in most cases there is an "s" mode and "w" mode standing for summer and winter. wherein the power delivery to the wheels is smoother in the "w" mode.

with regards to the cvt there is no downshifting per say since there are no gears. to quote a nearest example, try riding a gearless vario scooter at high speeds and try hard braking....the result will be similar to the cvt city. no engine braking.

thats a new one. i havent ever seen that. in most of the cars the s is for sport.:)

Hi funkydevil,

> just for the record my city has no abs.

The only model that has an ABS is the VTEC.

This is what 211 and 212 of the City owner manual says:

Drive (D)

Use this position for your normal driving. The transmission automatically adjusts to keep the engine at the best speed for driving conditions. To help the engine warm up faster, the transmission will select ratios that allow the engine to run at higher speeds when it is cold.

Second (S)

Selecting Second shifts the transmission into a lower range of ratios for better acceleration and increased engine braking. Use Second when you are going down a steep hill.

Low (L)

To shift ot Low, press the release button on the front of the shift lever. Use Low to get more power when climbing, and for maximum engine braking when going down steep hills.

For faster acceleration when in D, S or L, the transmission will automatically "kick down" to a lower range of ratios by pushing the acceelrator pedal to the floor.


> mode. I mean i donno how to explain it but, try putting a cvt city in s mode > n going from 0-100 u wont feel the gear change at all and the rpm is like
> always high, very high in fact some where arounnd 5000+. Altough the cvt > is a very smooth transmission when in 'D' mode u can feel the gears
> changing with a very slight jerk, (very slight) this is not so in the 'S' mode.

Please note that the S is referred to as Second and not Sport.

The best gearing in D mode is about 250rpm for every 10kph. The gearing in S mode is about 500rpm for every 10kph and so your observation of 5000rpm is correct. S is for overtaking and not to be used for regular driving as it will make a serious impact on fuel consumption.

> And yes in sports mode braking is more effective as unlike 'D' the gear
> change downards is just as fast as the gear change upwards.

The option during heavy braking is to flick the gear to S mode while braking which would increase the braking efficiency and once the speeds are down you could even go to L in an emergency.

I have not noted down the rpm speed relation in L mode, it could be at least 750rpm for every 10kph or more.

> By the way people in some of the forums, said since CVT is Continious
> Variable Transmission, the gear ratio's are unlimited as the transmission is
> variable unlike other automatics. I never got what this meant, n is this the > reason braking gets effected due to slow gear change.

This is correct. The gearing is automatically adjusted as per the vehicle engine load conditions. If you keep the vehicle at a fixed RPM, the speed would gradually rise to the best gearing possible and the vice versa.

In regular automatics also, the engine braking part is very less. So using the lower gears is the option to increase the engine braking during emergency braking.

Press clutch and break hard is not a good idea, as soon as you press clutch engine breaking is gone and car speeds up, better break hard and engine is about to stall press clutch as downshift, if you have time.

regards,
-manju

i used to wonder too what the "w" meant when "s" was obviously sport until i bought an auto transmission car and read its user manual.

if there is no "w" then yeah "s" stands for sport more but when there is also a "w", its clearly "s" for standard (not summer, i correct myself) and "w" for winter. i owned a merc c180 automatic for a few years and read the same in the user manual.

see link for confirmation.....

Automatic transmission

THATS BECASUE IT IS NOT CHANGING ABOVE 3RD !!!!!!!!!:deadhorse
FLOGG IT ALL YOU WANT,..CONTINUE DRIVING LIKE THIS AT 120 IN S MODE IN THE CITY CVT ,..YOU ARE ONLY GOING TO BLOW A GASKET FOR SURE !