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Old 2nd March 2008, 11:20   #31
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To those who are too worried about this , buy a car with lots of low end torque , preferably a diesel.
I too was once afraid, drove a diesel and was blown away by the low end grunt. Bought one - now I laugh at inclines
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Old 3rd March 2008, 17:35   #32
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Quote:
Originally Posted by nitrous View Post
This is DIY for simbali_sunny.Not for novices.
I'd suggest you take it to a knowledgeable mechanic.
you havnt forgotten "simbali" nitrous Anna.

Thanks to vikram_d for chipping in.

and regarding adjusting play in clutch i'm sure after 1 demo,most can do it.
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Old 3rd March 2008, 17:50   #33
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Default Half clutch with hand brake-

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Originally Posted by clevermax View Post
Rookies may also use the parking brake, but it is not a recommended way.

Hey I didn't know it was "not recommended" - in fact its the safest way to do it - particularly when either the car or driver is new and unsure of each other

They key is to not let engine drive forward and brake holding backward simultaneously - to avoid stress on engine, transmission and brakes

Further for expert drivers - half clutch - half brake +accelerator position is worth a try - learnt it while driving the padmini up the old khandala ghats - it was scary at first - but you eventually learn.

Rahul
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Old 3rd March 2008, 18:23   #34
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Quote:
Originally Posted by rahuldeodhar View Post
They key is to not let engine drive forward and brake holding backward simultaneously - to avoid stress on engine, transmission and brakes
How do you do that? Do you drive with hand brake engaged?
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Old 3rd March 2008, 22:09   #35
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Quote:
Originally Posted by greenhorn View Post
To those who are too worried about this , buy a car with lots of low end torque , preferably a diesel.
I too was once afraid, drove a diesel and was blown away by the low end grunt. Bought one - now I laugh at inclines
A small correction to your statement

Buy a diesel with common rail or at-least with turbo.
Buy NA diesel and the incline will be laughing at the car.
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Old 4th March 2008, 11:42   #36
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Default Using handbrake while starting on inclines

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Originally Posted by NetfreakBombay View Post
How do you do that? Do you drive with hand brake engaged?
I dont know if it was sarcastic or straight question. I dont know if the way I do it is technically correct or not but here goes.

Situation - The car/vehicle is parked (i.e. not moving/stationery) on an incline. You have foot on brake pedal & other on clutch. You can feel the car weight shifted toward rear

Recommendation-

1) Engage hand brake.

2)Release brake pedal see if car is moving back (it shouldnt be if hand brake is properly engaged) - all this while clutch is in pressed position - if everything is fine your one foot can now go to accelerator

3) Engage first gear

4) Depress the accelerator - clutch still engaged -revs should increase

5) gently release hand brake and clutch - judge carefully -watch for the "clutch bite" (explained earlier) and release brake completely as car weight transfers forward (indicating engine power kicking in)

This should do the trick

Recommendation using Half clutch half brake
1) Ease your right foot (brake foot) into a side-on position (toe-side on the brake pedal and foot rear free towards accelerator) - without lifting the foot

2) Push the accelerator with lower part of the foot - the revs should increase

3) release the brake while maintaining the accelerator level - simultaneously release clutch gently as engine power kicks in

This is terribly difficult - you have to practise it a lot to get it perfect. You invariably end up flooring the accelerator and if clutch is released the vehicle jerks to a halt.

Conversely hand brake version is easy to master also safer for newbies - and therefore - for all of us.

Half clutch halt -
This is equivalent of trying to hover in a normal aircraft
The clutch is half and accelerator is pressed slightly to keep the revs and brake is not used - this to my mind must cause lot of clutch wear and is risky as if concentration wavers you move on to person behind. Also if you are boxed in - vehicles moving in side lanes create an illusion that you are going behind -again need to concentrate hard for this.

Rahul
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Old 4th March 2008, 14:22   #37
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Quote:
Originally Posted by rahuldeodhar View Post
I dont know if it was sarcastic or straight question. I dont know if the way I do it is technically correct or not but here goes.
It was not meant to be sarcastic.. should have worded it differently.

Being a complete newbie to manual transmission cars I am facing these basic roadblocks. Thanks for the detailed answer.
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Old 6th March 2008, 13:34   #38
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No problem man! Just a mis understanding -

take care and drive safe!

RD
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Old 6th March 2008, 13:59   #39
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Quote:
Originally Posted by rahuldeodhar View Post

Situation - The car/vehicle is parked (i.e. not moving/stationery) on an incline. You have foot on brake pedal & other on clutch. You can feel the car weight shifted toward rear

Recommendation-

1) Engage hand brake.

2)Release brake pedal see if car is moving back (it shouldnt be if hand brake is properly engaged) - all this while clutch is in pressed position - if everything is fine your one foot can now go to accelerator

3) Engage first gear

4) Depress the accelerator - clutch still engaged -revs should increase

5) gently release hand brake and clutch - judge carefully -watch for the "clutch bite" (explained earlier) and release brake completely as car weight transfers forward (indicating engine power kicking in)

This should do the trick

Thanks for explaining my doubts as well.
One more question though.

Imagine you are waiting at the traffic signal. the traffic is just abt to start moving forward at a very very slow speed. How do you move your vehicle forward.

What I do is get into half clutch position without pressing the accelerator and then release the hand brake. Does this cause clutch wear?

Also, If I am stuck on an incline, I generally apply hand break with clutch fully depressed. When i am preparing to move, I get into half clutch and then release the handbrake, thus holding the car in position only on clutch...does this technique cause any extra damage to the clutch plates?

Regards,
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Old 6th March 2008, 14:44   #40
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Hi Mohit,

To understand clutch mechanism we can imagine our two palms in the "namaste" position - one palm - say left palm (also disc A) is driven by the engine in a rotational motion and other (right palm - or disc B)connected to a load (tyres in case of cars) - also imagine they are free to rev - i.e. rotate (like faces of Rubik cube)!!

Engine running means left palm is revving. And car is stationery means right palm is not revving. This means Left Palm and right palm are not touching each other. This is clutch dis-engaged position. Here there is no load on the engine.

Car running means the load (i.e. road friction / gradient etc) is transferred to the engine. It means left palm and right palm are in full face contact with each other. This is clutch engaged position. The namaste position!

When you are braking you apply force to the tyres (technically wheels /drums) and not to the engine. Here the force on our two palm is maximum as from one side you are revving left palm and other you are preventing right palm from revving WHILE - this is important - BOTH PALMS ARE IN CONTACT. Hence the high wear! (you can experience it by moving both palms in opposite direction while in contact - your palms will become warmer because of friction!)

Quote:
Originally Posted by amohit View Post
One more question though. Imagine you are waiting at the traffic signal. the traffic is just abt to start moving forward at a very very slow speed. How do you move your vehicle forward.
What I do is get into half clutch position without pressing the accelerator and then release the hand brake. Does this cause clutch wear?
keeping the hand brake on while releasing the clutch creates little more abnormal friction - hence its better if you release handbrake first and then do your half-clutch procedure
(this assumes the vehicle wont roll backwards when you release hand brake- else use procedure below)

Quote:
Originally Posted by amohit View Post
Thanks for explaining my doubts as well.

Also, If I am stuck on an incline, I generally apply hand break with clutch fully depressed. When i am preparing to move, I get into half clutch and then release the handbrake, thus holding the car in position only on clutch...does this technique cause any extra damage to the clutch plates?

Regards,
While on incline (imagine disc B revving in opposite direction as disc A) you want the forward forces (engine force) to overcome backward forces (car weight forcing you back) - hence by using hand brakes (i.e. preventing disc b from revving) friction should be lower than if you were to allow the vehicle to roll back before engaging the clutch - we need to remember that this is fine balancing

Just to highlight few things - Clutch damage (wear and stress etc) is high
#) when you let the engine experience sudden loads (thats why we "ease" the clutch)
#) when you let the discs slide (called slip) over each other for long durations - possible with improper setting
#) Clutch is friction based transfer of power hence clutch has to wear- that is what it is designed for - its only abnormal wear that we can avoid.

further Disclaimer - material overtly simplified hence dont expect to see two simple discs (they are a lot complicated).
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Old 6th March 2008, 15:21   #41
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In between the good discussion, I would like to jump in with a question
Quote:
When you are braking you apply force to the tyres (technically wheels /drums) and not to the engine. Here the force on our two palm is maximum as from one side you are revving left palm and other you are preventing right palm from revving WHILE - this is important - BOTH PALMS ARE IN CONTACT.
So you mean to say that the friction is maximum when we are applying brakes since we are trying to stop the rotation of the wheel wile the engine,still connected to the wheel continues to drive the wheel.

Now what I generally do is to apply brakes and slow the vehicle down without depressing the clutch till I feel mild vibration from the engine and then I depress the clutch to downshift. Am I doing it right or should I depress the clutch at the same time I am applying the brakes??
Which will cause more clutch wear?
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Old 6th March 2008, 15:50   #42
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Finally i adjusted the clutch and its much better now, it engages close to the half way of its travel. Thanx a lot vikram_d for helping me out.

But i feel that the clutch pedal position(when your foot is off ) has gone down a little bit.
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Old 6th March 2008, 16:11   #43
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I doubt if it would have gone down as it is connected to a spring and the spring ensures that the pedal comes back to its original position.
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Old 6th March 2008, 16:49   #44
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Default Clutch and Braking

Hi Praveen,

I was simplifying a rolling backward case - so in essence the situation is equivalent to applying accelerator and brake simultaneously.

Quote:
Originally Posted by praveen_v View Post
In between the good discussion, I would like to jump in with a question

So you mean to say that the friction is maximum when we are applying brakes since we are trying to stop the rotation of the wheel wile the engine,still connected to the wheel continues to drive the wheel.

Now what I generally do is to apply brakes and slow the vehicle down without depressing the clutch till I feel mild vibration from the engine and then I depress the clutch to downshift. Am I doing it right or should I depress the clutch at the same time I am applying the brakes??
Which will cause more clutch wear?
In your case we are in complicated territory. I am simplifying the step but its a complicated answer and you need to interpret this carefully. So here goes:-

First some notes:

#) In the hierarchy of importance - safety is paramount - so clutch friction can be ignored if it impedes safety. Safty comes through control - of speed and direction (since we are talking clutch here - we will ignore direction part)

#) High friction is not always bad - the judgement depends on the situation - we will look at a few situations below. But simply stated - When friction aids safety we opt for friction. When it impacts cost (through wear) without impacting safety we opt against it.

#) For every gear - for every engine - depending on the load conditions- there is a threshold speed. To take the car above this threshold speed you need to ride the accelerator. If you are riding above this speed - if you take the foot off the accelerator the car slows without having to brake.

#) When applying brake we do not floor/gun the accelerator (cant do it!)


Now lets examine the sitations - there are overrides mentioned below.

Dead Stop Situations
Situation 1: You are driving on or below threshold speed on plane (relatively - no incline) road and you want to stop.
#) Brake and start disengaging
#) Continue braking -whilst disengaged - till you come to standstill


Situation 2: You are going above threshold speed on relatively plane road and you want to come to a stop.
#) Brake with clutch engaged till you go below threshold speed/
#) Now disengage - still braking till you come to standstill


Situation 3: You are going uphill - you need to stop.
#) Remove accelerator see if threshold speed still makes you climb
#) brake and disengage simultaneously

Situation 4: You are going downhill - you need to dead stop
#) most important - DONT DISENGAGE! - its dangerous
#) brake and get the speed reduced to very creeping speed
#) as the car slows - then disengage watchfully- its ok if engine stops

Slow-down situations
Situation 5: You want to slow down on downhill -
#) Here too - DONT DISENGAGE
#) Here friction is your friend -opt for it

Situation 6: You want to slow down on plane road
#) Brake till you come below the threshold speed
#) Downshift gear to maintain control - disengage only for gear change
#) if you want to accelerate again - you can use accelerator and upshift
#) Note: This is complicated situation to be decided based on lot of factors


Overrides
#) In emergencies simply slam the brakes on! Dont worry about anything
#) Safety always comes before anything and everyhing

Your question does not have a direct answer hence I mentioned all this. Hope this answers your question.
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Old 6th March 2008, 17:04   #45
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And faulty spring can also cause the clutch to go Kaput.

so check it please and it should be a cheap part to change to get rid of any doubt.
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