Revving while moving off

Galbin

hasdanta wrote: »

Or you could just show the tester that there's no danger of you stalling on the hill start by successfully taking off without having to rev like mad..

Obviously, I learned that from the test. The point I was making was that I thought he would be happy for me to give it an extra rev in order to prove I would never fall down the hill. Nobody ever told me that they didn't like that.

Anyway, I'm sure there will be other instances of imperfection in the next torture test.

J_R

GarIT wrote: »

With the time it takes new drivers to do obs checks would this not destroy the clutch?

Absolutely not, in fact the opposite, as you will move off smoother, gain speed quicker, thereby the clutch will be fully engaged sooner where there is no wear.



I check if it’s safe to move off and then press the accelerator gently, release the clutch and release the handbreak all at the same time.

Synchronise three movements. ?. I used to be only half joking when I would tell my learners that they can not multi-task, can only do one thing at a time.

Hi,

J_R

beauf wrote: »

It's not about you, it's about unhappy revving.

As for diesels I think others have already explained it's not that simple as it's diesel or not.

I think the idea of setting a constant throttle level won't work the same depending on load or incline. So the use of varying throttle control is going to have to be intensively practiced to some one struggling with it.

I think clutch and throttle control varies massively between vehicles regardless if the principle is the same.

Hi,

From that statement I believe that you have never driven a modern diesel

beauf

J_R wrote: »

Hi,

From that statement I believe that you have never driven a modern diesel

According you you are car that can pull of from stopped in 3rd gear is the same experience as one that can't do it in first.

The fuel is irrelevant.

J_R

beauf wrote: »

According you you are car that can pull of from stopped in 3rd gear is the same experience as one that can't do it in first.

The fuel is irrelevant.

Do not understand. It is possible to move off, from stop , any car, petrol or diesel, in 3rd gear (or even higher).

However could be a little severe on the clutch.

J_R

beauf wrote: »

According you you are car that can pull of from stopped in 3rd gear is the same experience as one that can't do it in first.

The fuel is irrelevant.

Hi,

Yes it is. Well almost. In modern cars the only difference a driver will notice between petrol and diesel engines is that more revs needed in a petrol.

The reasons. Diesel engines are capable of higher compression ratios than petrol.

Compression is much higher with a diesel engine (14:1 to 25:1) than a gasoline engine (8:1 to 12:1).

Therefore each time a diesel fires it generates more power/torque than a petrol. To get the same torque in a petrol it is only necessary to increase the number of times it fires (or revs).

A good instructor that is using a diesel as a school car will explain the above to his pupils. He will teach them to always rev slightly before moving off, etc. so that when they change to a petrol car they will have no problems re stalling or controlling the car at slow speeds, for example when doing the turnabout.

A diesel engine is much heavier and more robust than a petrol but thanks to modern power assist techniques there is no noticeable difference in controlling it. So there is no extra pressure needed on, for example, the clutch.

beauf

There was a conversation about high torque petrols and low torque diesels with over sensitive throttle.

Saying one needs more revs then another suggests there is a difference, for the novice driver.

I already made the point one is far more fatiguing to drive in stop start traffic than the other.

J_R

beauf wrote: »

There was a conversation about high torque petrols and low torque diesels with over sensitive throttle.

Saying one needs more revs then another suggests there is a difference, for the novice driver.

I already made the point one is far more fatiguing to drive in stop start traffic than the other.

Hi
Have had my fair share of over sensitive pupils, God bless them, but never met or had to deal with an over sensitive throttle.

cantdecide

J_R wrote: »

Hi
Have had my fair share of over sensitive pupils, God bless them, but never met or had to deal with an over sensitive throttle.

Even in their own cars, no?

J_R

cantdecide wrote: »

Even in their own cars, no?

Hi,

No, and never ever came across a car with an over sensitive throttle or even someone using the excuse that their car had an over sensitive throttle.

If I did, can think of just three possible cures
Change Footwear
Get car serviced
Get a driving lesson with a competent instructor

beauf

Modern throttles can be updated through software updates, there's been some recalls with throttles. But if a car has low torque at low revs or a peaky power delivery not much is going to change that... Other than shoes... Obviously.