Brake Gear Overlap Downhill Prior to left turn

[geot1]

I appreciate much has been written on the issue of Brake Gear Overlap already, and so I know in which circumstances it can be used, but would appreciate some clarification on a technical point in this scenario - turning into a narrow road (sharp left turn) with a downhill gradient prior to the turn. Say a 1st gear was the required gear for this turn.

Now, to keep it simple, if I was in 2nd gear and needed to change down, in light of the fact it is downhill, I would brake while the clutch is down and I am changing gear. I understand this.

What I am unsure on is whether I can keep my foot lightly on the brake as I lift the clutch back up again, to engage 1st gear. I have heard from some people that it is best to take the foot off the footbrake while lifting clutch back up to engage the lower gear,but the danger on the hill is that you will pick up a bit of speed again, before this sharp turn.
Some clarification on this detail would be appreciated.

In fact, I assume the case would be the same for a 2nd gear turn as well, changing down from 3rd - I am just interested if the brake can be fully overlapped, during and coming out of the gear change down.

Obviously as well, this would all be done fairly quickly just before the left turn, but I think the hard bit is finding the balance between changing too early before hazard, and too late running the risk of clutch down - coasting - whilst taking the turn i.e. letting yourself get on top of the hazard.

[Dave Hedgehog]

turn in on the brake, handbrake into the corner, power down as the back comes round

[Wattsie]

Dave Hedgehog said:

turn in on the brake, handbrake into the corner, power down as the back comes round

This.

[thiscocks]

yes you can engage the gear with foot fully on the brake. Best to have the gear selected before you turn though (clutch fully engaged). For 1st gear you might have to heel and toe a bit if your going much faster than walking pace.

[Ozzie Osmond]

I've been driving for more than a decade and don't recall ever feeling the need to change down into first gear when on the move.

[geot1]

The 1st gear was an example - I am concerned with the principle of overlap - it could well be changing down to a 2nd gear from 3rd/4th etc.

But regarding 1st gear, on some vehicles, a failure to select 1st gear on a very tight turn (near to a stopping speed virtually) would result in stalling. There are times.s

[catman]

Yes, of course it's ok to brake until you've released the clutch pedal. You can continue to brake afterwards too, if needed.

With reference to which gear, it depends entirely on the car that you're driving! It's simply down to which gear on that particular car is most suitable for the speed required to make the turn safely.

Tim

[Ozzie Osmond]

There is no problem braking and changing down simultaneously. It's one of the main reasons why your gearbox is fitted with synchromesh.

"A modern automobile has a synchronizer mechanism or synchromesh, which consists of a cone clutch and blocking ring. Before the gear teeth can engage, the cone clutch engages first which brings the selector and gear to the same speed using friction. Moreover, until synchronization occurs, the teeth are prevented from making contact, because further motion of the selector is prevented by a blocker (or baulk) ring. When synchronization occurs, friction on the blocker ring is relieved and it twists slightly, bringing into alignment certain grooves and notches that allow further passage of the selector which brings the teeth together. Of course, the exact design of the synchronizer varies from manufacturer to manufacturer."

By the way, don't drive a synchro car without using the clutch. Your attempts will appear OK but in reality the synchros are doing much more work than they were designed for. Always use the clutch.

[geot1]

Thanks all. So from the comments, it seems that it is perfectly ok to keep foot on footbrake whilst lifting clutch back up to engage lower gear. So the brake can be used before, during and after changing down a gear for the required hazard..in a planned manoeuvre, on the grounds of safety.

[Fastdruid]

Ozzie Osmond said:

I've been driving for more than a decade and don't recall ever feeling the need to change down into first gear when on the move.

You've obviously never driven a 318d then.

[kaf]

geot1 said:

Thanks all. So from the comments, it seems that it is perfectly ok to keep foot on footbrake whilst lifting clutch back up to engage lower gear. So the brake can be used before, during and after changing down a gear for the required hazard..in a planned manoeuvre, on the grounds of safety.

Your last sentence says it all.............it is the only safe way of doing it, keep that foot on the brake, perfectly acceptable.

[Pugsey]

And of course while doing all of the above you'll also be rev matching with the throttle won't you since gravity 'pushing' or trying to accelerate the car down the hill will tend to require just a little more in the way of revs than if you were changing on the flat.

[MC Bodge]

I don't think that 'Advanced Driving' is intended to make life difficult, but attempting to adhere to the basic 'rules' at all costs and in all situations would be very difficult. Roadcraft does acknowledge that there are times that overlapping braking and shifting is beneficial (and even acknowledges that overlapping can be quicker!, even if it doesn't regard it as desirable).

There is a definite need for interpretation whilst driving and not just blindly following rules in the manner of a soldier following orders. Preventing the car gaining speed by braking during down-shifting on a steep hill is fine (-trying it on a wet, slippery, downhill hairpin on a motorbike is interesting...)

Of course, if you live in a flat area and always drive like a Roadcraft (Old Testament) Fundamentalist, you'll be a bit flummoxed in this situation as you will not have practised any dangerous multi-tasking....

I suggest practising heel-and-toe to get a reasonable degree of proficiency, so you'll then be able to cope with a challenging mountain pass better than the vast majority of drivers.

Edited by MC Bodge on Tuesday 10th January 12:18

[MC Bodge]

Ozzie Osmond said:

I've been driving for more than a decade and don't recall ever feeling the need to change down into first gear when on the move.

I've been driving for getting on for 2 decades and recall numerous occasions when I have changed down into first gear whilst on the move.

[Pugsey]

MC Bodge said:

I don't think that 'Advanced Driving' is intended to make life difficult, but attempting to adhere to the basic 'rules' at all costs and in all situations would be very difficult. Roadcraft does acknowledge that there are times that overlapping braking and shifting is beneficial (and even acknowledges that overlapping can be quicker!, even if it doesn't regard it as desirable).

There is a definite need for interpretation whilst driving and not just blindly following rules in the manner of a soldier following orders. Preventing the car gaining speed by braking during down-shifting on a steep hill is fine (-trying it on a wet, slippery, downhill hairpin on a motorbike is interesting...)

Of course, if you live in a flat area and always drive like a Roadcraft (Old Testament) Fundamentalist, you'll be a bit flummoxed in this situation as you will not have practised any dangerous multi-tasking....

I suggest practising heel-and-toe to get a reasonable degree of proficiency, so you'll then be able to cope with a challenging mountain pass better than the vast majority of drivers.

Edited by MC Bodge on Tuesday 10th January 12:18

Good stuff - especially re h&t.

[Pugsey]

MC Bodge said:

Ozzie Osmond said:

I've been driving for more than a decade and don't recall ever feeling the need to change down into first gear when on the move.

I've been driving for getting on for 2 decades and recall numerous occasions when I have changed down into first gear whilst on the move.

Indeed. Quite a few well know 'drivers' passes in Europe require 1st - in any car - at least once per climb.

[MC Bodge]

Pugsey said:

MC Bodge said:

Ozzie Osmond said:

I've been driving for more than a decade and don't recall ever feeling the need to change down into first gear when on the move.

I've been driving for getting on for 2 decades and recall numerous occasions when I have changed down into first gear whilst on the move.

Indeed. Quite a few well know 'drivers' passes in Europe require 1st - in any car - at least once per climb.

Indeed they do. As do quite a few lanes in hilly areas, and even multi-storey car parks, in the UK....

[BertBert]

Pugsey said:

MC Bodge said:

I suggest practising heel-and-toe to get a reasonable degree of proficiency, so you'll then be able to cope with a challenging mountain pass better than the vast majority of drivers.

Good stuff - especially re h&t.

Whilst H&T would have advantages if whanging down a mountain pass, it's not specifically relevant to the situation the OP described. The competent advanced driver should be technically able to make smooth changes without rev-matching when overlapping is called for. As my 17 year old daughter can do perfectly adequately.
Bert

[kaf]

BertBert said:

Whilst H&T would have advantages if whanging down a mountain pass, it's not specifically relevant to the situation the OP described. The competent advanced driver should be technically able to make smooth changes without rev-matching when overlapping is called for. As my 17 year old daughter can do perfectly adequately.
Bert

Quite, instead of bringing the revs up to match the road speed, get the road speed down to match the intended gear.

[MC Bodge]

BertBert said:

Whilst H&T would have advantages if whanging down a mountain pass, it's not specifically relevant to the situation the OP described. The competent advanced driver should be technically able to make smooth changes without rev-matching when overlapping is called for. As my 17 year old daughter can do perfectly adequately.
Bert

I agree, but having the ability to heel-toe or blip the twist-grip under braking, helping to maintain balance and smoothness, is very useful and can take one's driving or riding beyond that of most people.

...and what kind of peculiar keen driver(or rider) would not enjoy "whanging down a mountain pass"???


Roll on Summer ...and a lottery win

Edited by MC Bodge on Tuesday 10th January 13:37