Advanced Driving Hub

TBH, the 'deeper' into content it went, the less I enjoyed it. However, foal found it interesting, so it was worth it for that (albeit I borrowed it ).

Horse wrote:Sounds the same, then! No attempt at rev-matching, so reliant on either the vehicle pulling from tickover or the selected gear pulling up the revs to a usable level (presuming that a usable gear is selected appropriate to the road speed).

How could that be better than keeping the left foot on the clutch long enough to have the right foot on the accelerator for a little rev matching while raising the clutch?

waremark wrote:

Horse wrote:
Sounds the same, then! No attempt at rev-matching, so reliant on either the vehicle pulling from tickover or the selected gear pulling up the revs to a usable level (presuming that a usable gear is selected appropriate to the road speed).

How could that be better than keeping the left foot on the clutch long enough to have the right foot on the accelerator for a little rev matching while raising the clutch?

Sorry, I don't know what you mean. In the DVD he doesn't apply any throttle until after both feet are lifted, simultaneously, off the clutch and brake pedals - as described in the quote from Von earlier in the thread.

Horse wrote:

waremark wrote:

Horse wrote:
Sounds the same, then! No attempt at rev-matching, so reliant on either the vehicle pulling from tickover or the selected gear pulling up the revs to a usable level (presuming that a usable gear is selected appropriate to the road speed).

How could that be better than keeping the left foot on the clutch long enough to have the right foot on the accelerator for a little rev matching while raising the clutch?

Sorry, I don't know what you mean. In the DVD he doesn't apply any throttle until after both feet are lifted, simultaneously, off the clutch and brake pedals - as described in the quote from Von earlier in the thread.

Yes, but why? It doesn't sound ideally smooth or sympathetic.

Why not declutch while braking if necessary to prevent the engine from labouring, and hold the clutch down until after completion of the braking phase, then and only then raise the clutch while also applying an appropriate amount of acceleration for rev matching?

If the issue is that we are on a very steep hill and don't want the car to run away the moment we release the brake, then why not raise the clutch a moment before completion of the braking phase?

Aah, von's artic.
Try it, when in a quiet area. I have.

waremark wrote:

Horse wrote:

waremark wrote:

Horse wrote:
Sounds the same, then! No attempt at rev-matching, so reliant on either the vehicle pulling from tickover or the selected gear pulling up the revs to a usable level (presuming that a usable gear is selected appropriate to the road speed).

How could that be better than keeping the left foot on the clutch long enough to have the right foot on the accelerator for a little rev matching while raising the clutch?

Sorry, I don't know what you mean. In the DVD he doesn't apply any throttle until after both feet are lifted, simultaneously, off the clutch and brake pedals - as described in the quote from Von earlier in the thread.

Yes, but why? It doesn't sound ideally smooth or sympathetic

Hence my Q in post #1

It didn't make sense to me either.

WhoseGeneration wrote:Aah, von's artic.
Try it, when in a quiet area. I have.

Needs a lot of space, tho.

Full overlap is easy really, and if done correctly is perfectly smooth and does not de-stabilise the vehicle.

It gets bad press because most drivers do not slow sufficiently going into the hazard, something which would be clumsy and lead to poor control with full separation. There for full separation forces the driver to slow, whereas full overlap allows the driver to remain on the brakes longer allowing them to approach faster provided that the driver doesn't need to steer at the same time. For an advanced driver whichever method is used should be no problem as they should be disciplined enough to get the speed down to the correct speed for the hazard.

So how do we go about overlapping? Unless you can heel and toe, you must stay on the brakes and only declutch at the point just before the engine revs drop to the point when the engine starts to labour. Declutch and engage the relevant gear. As the clutch returns to the biting point release the brake and the engine can then hold the vehicle using engine compression for a downhill turn, the driver may also have to stay on the brakes as engine braking alone may not be sufficient. If it is not necessary to remain on the brake, the right foot returns to the accelerator to drive the vehicle.

I have always found that doing the above is very smooth. The main thing is that the driver keeps the vehicle under full control and is disciplined enough to get the speed down to the correct speed for the hazard to be negotiated.

My thoughts are that full separation harks back to the days of non synchromesh gear boxes when the driver had to separate, unless they could heel and toe or do clutch less gear changes.

Nigel.

Ta. Good explanation.

I like the final sentence of Fungus's last post in which he thinks that full separation of braking and changing gears dates back to the days of non-synchromesh gearboxes. I believe him to be correct.

For me, one of the huge bonuses of the system is that it works for any vehicle: for example, I take up the same positions when cornering a motorcycle as I would in an artic, and likewise I reduce speed before a bend and pick up the drive prior to entering it both on a bike and when driving a truck. These are just two examples, and these vehicles being at the extreme ends of the stability spectrum prove the system to be correct. Lots of car drivers get away with their bad habits only because the vehicle itself is inherently stable and not that heavy.

The next phase of my argument is that if one can separate braking and changing gear then one can jump into a vehicle with a crash gearbox and drive the thing. If you cannot get rid of a BGOL, then trying to drive such a vehicle is going to result in a great deal of embarrassment. The right way is the right way because it works in any and every vehicle. Any system, or method of vehicle control, that works for some vehicles and not others is not much of a system.