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Old 17th March 2010, 22:05   #31
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@ mayukh

The driving school m800 where I learnt driving and my uncle's omni never moved without giving a bit of throttle. But its different in my car, all I need to do is just let go of the clutch and it moves forward.
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Old 17th March 2010, 22:12   #32
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I am yet to look at Beat spec - but is it not true that MPFI cars generally move when clutch is just released (no gas at all) ? If that's the case should not all modern cars do this by default or NO ?

Can somebody clarify to another noob here ?
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Old 17th March 2010, 22:37   #33
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Infact when the rpm is higher, few petrol cars start on zero accelration/release of clutch. For sake of observation, cold start the vehicle in the morning and release the clutch alone, the vehicle moves since the rpm at cold is around 1300-1350 and settles down at 800 when the engine is heated up to its optimal temperature

Increasing the idling reduces the mileage and hence not advisable
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Old 17th March 2010, 22:43   #34
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Quote:
Originally Posted by mayukh View Post
I have an opposite story to tell.

I was taking driving lessons back in Dec '09 in any of my 3 driving school cars - Alto, Santro, Esteem. The clutch in Santro was to some extent OK. However, the clutches in Alto & Esteem were so notorious that the cars used to stall whenever I was not following
+1. Clutch in Alto is one of the worst clutch for a small car. Ironic isn't it? It's a small car, supposed to be easy to drive car but sadly it isn't.

Quote:
Originally Posted by Mr_Bean View Post
cold start the vehicle in the morning and release the clutch alone, the vehicle moves since the rpm at cold is around 1300-1350 and settles down at 800 when the engine is heated up to its optimal temperature
In my car, rpm at start is 1500, but it settles down to somewhere between 800 and 900 within 4 seconds or so. I don't know how it can be of any advantage to start off from standstill. If your engine has good torque to offer at lower rpm, then it is easy to start moving without pressing gas pedal. You should have a smooth clutch as well.

Last edited by clevermax : 17th March 2010 at 22:46.
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Old 18th March 2010, 13:01   #35
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Quote:
Originally Posted by vj_carLover View Post
I am yet to look at Beat spec - but is it not true that MPFI cars generally move when clutch is just released (no gas at all) ? If that's the case should not all modern cars do this by default or NO ?

Can somebody clarify to another noob here ?
VJ,

I will try to clarify, which is a combination of all the factors already discussed.

For simplicity lets breakup your questions into two components.

1) Yes all modern MPFI cars have the idle speed preset at 800 - 900. So the start base is same on all cars. This is at no load (No AC,Power steering ets)

Now lets analyse the second component. Why dont all cars move without accelerating

2) As already discussed, any movement is impeded by the amount of load to be displaced, so we are applying lets say 'X' amount of force to displace a load. The amount of force applied varies on each car/situation.
For ex you can have 2 cars of the same make, one parked on upward incline and the other car on a flat surface. Though the intial force applied will be the same, but the movement for the car on the incline will happen only by adding additional force. Now lets add some complexity to this, Lets take an example of two cars of different make same engine capacity but on a flat surface. Here again one car may move and the other may not because of (A) weight difference which may add to the load (B) Low end torque (Read that as gear ratio's) etc.
One more indication of the load would be observe the RPM speed once the clutch is released (with out accelerating).


Hope the above clarifies. Anyone else is free to add or correct

Last edited by kiranpashtakar : 18th March 2010 at 13:06.
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Old 18th March 2010, 22:25   #36
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Wow. This thread touches precisely the point I'm always confused about.

I'll write what I understand and it'd be great if anybody could verify it's correctness.

1. While starting the car, the clutch should be fully depressed.
2. Using an accelerator which releasing the clutch at 0 speed may be optional in some cars and may not be so in others.
3. Use the clutch as less as possible. This prevents wear.

My questions:-

1. How much of the clutch needs to be depressed
a) when starting from speed 0 km/h ?
b) when shifting gears ?

2. If you need to move slower than the idle speed of your car, is there any other option than riding the clutch ?

3. What should be the clutch release mechanism while shifting gears ? Sudden or gradual ? I sometimes get jerks on sudden release, but if I use gradual release, sometimes the speed falls below the range of the gear I'm shifting to.

4. What is the range of action of a clutch ? Is there any point in fully depressing a clutch ?

5. How does a clutch in a used/old car differ from one in a new car ?

Sorry for the no. of questions, but it gets real confusing at times.
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Old 18th March 2010, 23:37   #37
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Quote:
Originally Posted by kiranpashtakar View Post
VJ,

I will try to clarify, which is a combination of all the factors already discussed.

For simplicity lets breakup your questions into two components.

1) Yes all modern MPFI cars have the idle speed preset at 800 - 900. So the start base is same on all cars. This is at no load (No AC,Power steering ets)

Now lets analyse the second component. Why dont all cars move without accelerating

Hope the above clarifies. Anyone else is free to add or correct
Thank you @kiranpashtaka for taking the time and a patient explanation. I have a Maruti estilo, and car moving with just the clutch control is a boon for me in bumper-bumper traffic.

One thing thoug, I hope this would not cause a "clutch wearout", me asking because, accelerator pedal is not used and wouldn't this count as "half clutch" ?

Appreciate the answers

Cheers
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Old 19th March 2010, 09:57   #38
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With my limited understanding & experience:

Quote:
Originally Posted by anku94 View Post
Wow. This thread touches precisely the point I'm always confused about.

I'll write what I understand and it'd be great if anybody could verify it's correctness.

1. While starting the car, the clutch should be fully depressed.

2. Using an accelerator which releasing the clutch at 0 speed may be optional in some cars and may not be so in others.

3. Use the clutch as less as possible. This prevents wear.

My questions:-

1. How much of the clutch needs to be depressed
a) when starting from speed 0 km/h ?
b) when shifting gears ?
Fully

2. If you need to move slower than the idle speed of your car, is there any other option than riding the clutch ?
If you are higher gears and not a right speed, the rpm dips below idle & engine starts knocking eventually switching off. In bumper 2 bumper traffic of speeds less than 5km/hr, i have felt there is no other options other than riding the clutch.

3. What should be the clutch release mechanism while shifting gears ? Sudden or gradual ? I sometimes get jerks on sudden release, but if I use gradual release, sometimes the speed falls below the range of the gear I'm shifting to.
You need to match the revs, So start giving acceleration at the very end of the clutch release. I got rid of this jerk by doing that.

4. What is the range of action of a clutch ? Is there any point in fully depressing a clutch ?
Fully depress the clutch, I know a friend who damaged his gearbox when he tried to shift gears by not depressing the clutch fully..

5. How does a clutch in a used/old car differ from one in a new car ?
Worn out clutch - speeds don't match the revs, low pickup, low mileage.

Sorry for the no. of questions, but it gets real confusing at times.
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Old 19th March 2010, 13:26   #39
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Thanks a lot, Mr. Bean
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Old 15th September 2016, 19:27   #40
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Default Re: Things they donít teach you at an Indian driving school

Recently I joined a driving class and after a few days I am into the "Gears". My instructor made me roll into first, second, third, fourth and combinations there of while standing so that I know the positions. Later on I was instructed to ride in the first and second as higher gears will be taken care later on.

Is this a common observance at the initial days while riding? I think that the clutch is damn hard as compared to the showroom Tiago.

P.s. :- While taking turns at busy junctions I came to know what is A pillar obstructions.

Last edited by SDP : 16th September 2016 at 19:51. Reason: Hard-clutch portion reinstated after moving
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Old 15th September 2016, 19:36   #41
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Default Re: Things they donít teach you at an Indian driving school

Quote:
Originally Posted by Majumdarda View Post
Recently I joined a driving class and after a fe.

Is this a common observance at the initial days while riding? I think that the clutch is damn hard as compared to the showroom Tiago.

P.s. :- While taking turns at busy junctions I came to know what is A pillar obstructions.
If you call the WagonR clutch heavy, either the WagonR has a really messed up clutch, or you are really underestimating what a 'hard' clutch is. My K10 wagonr had a really light clutch and when I tried the clutch of our D-BHPian Parag Sachania's 2.2L km done F10 wagonr, the clutch just sunk in with the weight of the foot.

Speak about this issue with the driving school. Let them provide an alternate vehicle or get the clutch fixed. I had the chance to sit in a driving school wagonR when I appeared for Autocar young driver, and the clutch was again light and was completely dead with no feedback and biting point. Yet it wasnt hard of any sort.
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Old 15th September 2016, 20:32   #42
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Quote:
Originally Posted by audioholic View Post
...
That answers my concern. I doubt they will do any modifications. Its probably kept that way intentionally. Also there are no alternate car options here.

These learning classes are good till the extent where one can drive his brand new car from showroom to home. For skill development etc, I believe one has to learn on their own.
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Old 15th September 2016, 21:00   #43
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Default Re: Things they donít teach you at an Indian driving school

I imagine that driving-school cars are really punished.

Imagine the grinding sounds as a novice learns to use clutch and gears. Now imagine that happening to the same car, day after day after day.

Maybe this is car hell! Being reborn in a driving school!
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Old 15th September 2016, 22:32   #44
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Quote:
Originally Posted by Majumdarda View Post
...Is this a common observance at the initial days while riding?...
Yes it is. I still remember my first few days with the driving school car. My legs were so sore and stiff, but I didn't give up. (I'm sure you wouldn't too).

Welcome to the world of driving. It's just that our muscles aren't used to these new set of controls. You'll be comfortable with the whole thing very soon.
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Old 16th September 2016, 11:11   #45
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Default Re: Things they donít teach you at an Indian driving school

Learning on your own is always possible and would be even better if you had an experienced knowledgeable friend to guide you.

Another possibility is to walk into a Maruti dealership and inquire about the Maruti Driving school. Although I knew how to drive at a very early age, my parents put me in the Maruti Driving School, mainly because they sorted out my driving license for me. I did have to drive with an instructor for a couple of days and then till the driving test and I found the cars to be kept in pretty good shape considering what they must be going through. I did notice a lot of terrible drivers including one woman who wasn't even able to judge spaces and traffic around her (and she was on her way to the driving test with me at the same day ), the instructor kept joking about her driving skills when the fact was that in one whole month he was the one who wasn't able to do his job properly and teach her enough, so don't expect any professional care or anything of the sort you may need to be proactive about it.

Last edited by SDP : 16th September 2016 at 12:26. Reason: Quoted post deleted.
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