Current thoughts on brake-gear overlap (BGOL)?

[Scott OSRS]

Just wondering what the current consensus is on brake gear overlap, as I’m reading conflicting things from different IAM groups.

The Guildford IAM group seem to say avoiding it is a thing of the past, and you should instead aim to avoid brake-steer overlap: https://guildford-iam.org.uk/wp-content/uploads/20...

Whereas Bristol IAM seem to still encourage avoiding it: https://www.iam-bristol.org.uk/index.php/articles/...

Edited by Scott OSRS on Monday 27th February 16:51

[otolith]

linky said:

On the subject of brake gear overlap the course material
says simply: “Understand when a planned overlap is appropriate. At slow speeds for simple
junctions it will be safe to overlap brakes and gears. The gear change needs to be finished and the
clutch engaged before steering.”
Hopefully that is clear, applying all the principles in the evolution of Roadcraft and condensing it to
a succinct statement. So no longer shall we speak of ‘brake gear overlap’ now we will talk of ‘brake
steer overlap.’

Not sure how he got "brake steer overlap" from "gear change... before steering" - suspect that turning in as you ease off the brake having downshifted using H&T might be frowned upon as track driving heresy, but it doesn't actually say that.

[waremark]

I think there is a widespread attitude that it is too difficult to avoid BGOL and the benefits are too marginal so we won't worry about it. I had a Masters Mentee who had scored a first without knowing about rev matching.

But of course attitudes vary from Observer to Observer and Examiner to Examiner, let alone from Group to Group.

[johnao]

waremark said:

I think there is a widespread attitude that it is too difficult to avoid BGOL and the benefits are too marginal so we won't worry about it. I had a Masters Mentee who had scored a first without knowing about rev matching.

But of course attitudes vary from Observer to Observer and Examiner to Examiner, let alone from Group to Group.

BGOL is acceptable on IAM test provided it is planned and incorporated into the system such that it gives you an advantage over brake/gear separation. Situations where planned BGOL is acceptable would include downhill into a bend, and when turning left into a side road when you have a massive truck in your rear view mirror and the truck driver is not going to allow you the luxury of slowing sufficiently to nicely execute the perfect brake gear separation.

[waremark]

johnao said:

waremark said:

I think there is a widespread attitude that it is too difficult to avoid BGOL and the benefits are too marginal so we won't worry about it. I had a Masters Mentee who had scored a first without knowing about rev matching.

But of course attitudes vary from Observer to Observer and Examiner to Examiner, let alone from Group to Group.

BGOL is acceptable on IAM test provided it is planned and incorporated into the system such that it gives you an advantage over brake/gear separation. Situations where planned BGOL is acceptable would include downhill into a bend, and when turning left into a side road when you have a massive truck in your rear view mirror and the truck driver is not going to allow you the luxury of slowing sufficiently to nicely execute the perfect brake gear separation.

That's the Roadcraft approved approach. I believe that most Observers and Examiners are tolerant of B.OL without those good reasons. Am I wrong?

When Observing for IAM, other than in those circumstances, I advocate and demo separation (finishing braking before starting to change gear, and finishing the gear change before starting to steer), However, when driving without those constraints I personally get more satisfaction from changing gear while still braking using H & T to rev match accurately.

[johnao]

waremark said:

That's the Roadcraft approved approach. I believe that most Observers and Examiners are tolerant of B.OL without those good reasons. Am I wrong?.

The examiners will always say it has to be planned. It may be the case that what appears to be tolerance may actually be obliviousness. BGOL at low speeds with modern clutches can be smooth and almost imperceptible. This is not the case at higher speeds unless one uses H&T.

[billbring]

Can I ask what exactly is the correct sequence of controls that is deemed to not be overlapping brakes and gear?

A) apply brake, clutch down, change gear, release brake, clutch up

or

B) apply brake, release brake, clutch down, change gear, clutch up



I've tried both and B feels very unnatural but (I believe) is the correct answer.

I typically do A and I can't understand what the disadvantage of this is - the right foot is off the brake before the clutch is released so can rev-match if necessary.

[wyson]

Brake gear overlap is the first thing I started doing when I passed my IAM test and only reserve separating them for really treacherous conditions.

In a modern car with ABS, power steering, modern clutches and synchromesh gearboxes, you are driving straight, good road conditions and visibility, I can’t see avoiding brake gear overlap bringing any benefit whatsoever.

Second thing I dropped is road positioning on most bends. Like on a wide sweeping A Road, literally brings zero benefit at sane speeds. Perhaps if you were going 150mph, I could see where that split second extra reaction time / visibility might be beneficial. In the mean time, you are stressing because of debris and getting a puncture. Pointless. Occasionally, I do think, oh, whats round there, I need a better look and position the car accordingly, but act on this mental prompt, rather than do it as a rule.

I think on your test, if you demonstrate both BGOL and avoiding BGOL with commentary explaining why, it will be totally fine. Could play it safe and not do it at all. I wanted to give all the IAM techniques a proper bash so for my practice sessions and test didn’t BGOL at all.

Edited by wyson on Tuesday 21st March 21:17

[thumb5]

billbring said:

Can I ask what exactly is the correct sequence of controls that is deemed to not be overlapping brakes and gear?

A) apply brake, clutch down, change gear, release brake, clutch up

or

B) apply brake, release brake, clutch down, change gear, clutch up

There's also:

C) apply brake, [keep braking to reduce speed until desired speed is reached or need to de-clutch to keep engine happy], clutch down, [keep braking if necessary to reduce speed further], release brake, change gear, clutch up

That's how I understand "no BGOL", after struggling to put (B) into practice. This approach feels quite natural to me (after some practice) and is in line with the IPSGA mantra, possibly depending on your interpretation. Reg Local has a video on this topic which I found very helpful.

[M4cruiser]

thumb5 said:

billbring said:

Can I ask what exactly is the correct sequence of controls that is deemed to not be overlapping brakes and gear?

A) apply brake, clutch down, change gear, release brake, clutch up

or

B) apply brake, release brake, clutch down, change gear, clutch up

There's also:

C) apply brake, [keep braking to reduce speed until desired speed is reached or need to de-clutch to keep engine happy], clutch down, [keep braking if necessary to reduce speed further], release brake, change gear, clutch up

That's how I understand "no BGOL", after struggling to put (B) into practice. This approach feels quite natural to me (after some practice) and is in line with the IPSGA mantra, possibly depending on your interpretation. Reg Local has a video on this topic which I found very helpful.

After taking IAM training I was doing (B) myself. And have been ever since (until I bought an automatic).
It keeps the car balanced better (arguably). H&T requires a lot more work to keep the car balanced.
But
All of (A) (B) & (C) are better than what most "ordinary" drivers do:-
(D) Apply brake, clutch down, change gear, clutch up, keep braking, clutch down, change gear again, clutch up, brake some more, clutch down, steer round the corner/junction, change gear, release brake, clutch up and go. Yuk.

[Pica-Pica]

We are really looking at control and stability of the vehicle. To me that is the important thing. If I wish to brake and change down at the same time, I will, as long as it is smooth and the vehicle accommodates it comfortably. The issue missed in this is the brake stop light signal you are showing to following vehicles. Do you want a constant signal or an intermittent one? What do want them to take in and understand? This is also where block changing will help.

[_Hoppers]

For me, avoiding BGOL highlights inadequacies in limit point analysis whether it be not understanding or applying it correctly. When separating brake and gears you have to get your speed set 'well' before the corner and if the trainee hasn't it becomes plainly obvious, especially if secondary braking is required. When using BGOL I think it is easier to hide the fact that limit point analysis has not been properly observed. Separating brake and gears also allows the trainee to perform a rev matched gear change without the need for heel and toe. One of the downsides to separating brake and gears can be at junctions in built up areas, you need to get your speed down early and this can confuse other road users. I have had someone turn across my path as they thought I was slowing to let them pass, which was not the case. As a result of this I generally don't separate brake and gears in built-up areas (when I'm driving my wife's car, mine is an auto!).

Edited by _Hoppers on Wednesday 22 March 09:14

[waremark]

_Hoppers said:

Separating brake and gears also allows the trainee to perform a rev matched gear change without the need for heel and toe.

Edited by _Hoppers on Wednesday 22 March 09:14

Have you ever had an Associate who was good at Heel and Toe? What would you say to them?

I haven't ever had an Associate who uses H & T. Personally, I do so fairly routinely and think it contributes to a smooth flowing mechanically sympathetic drive. However, when giving a demo to an associate I avoid overlap - generally in the fullest sense of finishing braking before moving hand from wheel to gear lever and left foot from foot rest to clutch in parallel with the right foot moving from brake to accelerator. Downhill or into a junction with someone close behind I do the partial overlap of finishing braking just before letting the clutch out in the new gear.

[_Hoppers]

waremark said:

_Hoppers said:

Separating brake and gears also allows the trainee to perform a rev matched gear change without the need for heel and toe.

Edited by _Hoppers on Wednesday 22 March 09:14

Have you ever had an Associate who was good at Heel and Toe? What would you say to them?

I haven't ever had an Associate who uses H & T. Personally, I do so fairly routinely and think it contributes to a smooth flowing mechanically sympathetic drive. However, when giving a demo to an associate I avoid overlap - generally in the fullest sense of finishing braking before moving hand from wheel to gear lever and left foot from foot rest to clutch in parallel with the right foot moving from brake to accelerator. Downhill or into a junction with someone close behind I do the partial overlap of finishing braking just before letting the clutch out in the new gear.

I used to tutor for bikes not cars so my post was based hypothetically if I was a car tutor. I've not tutored for a number of years and since doing my RoSPA car test it appears, from posts here, that BGOL is becoming generally accepted? If I did tutor for cars, and BGOL was encouraged by the group/examiners, I'd still like to see the trainee demonstrate both approaches. I'd prefer separation as it provides a smoother gear change and demonstrates a mechanically sympathetic skill. With regard H&T and bearing in mind the advanced tests are focussed on safety, I think it is a potentially an unsafe procedure. For me personally I do both, usually I'll BGOL (with a heel/toe) when 'pressing on' a bit!

EDIT: I've just re-read my previous post and I should have said 'For me, avoiding gear separation can highlight inadequecies....'!!

Edited by _Hoppers on Thursday 23 March 12:42

[DashDriver]

The way it was explained to me was it is not strictly necessary on a modern car, that's not to say learning to do it in safe smooth and systemic way is a useful skill. It creates clear separation when starting to learn system and you have to have what I was taught was a PLAN BACK so when dealing with a Hazard you plan you approach and do everything in a staged and systematic way.


I think once you have mastered it you can, move to heel and toe if the car is balanced and its to system (more advanced polished drive)


I believe it was more applicable when Roadcraft was first written as cable brakes were not very forgiving when braking and trying to turn and the vehicle was unstable , so it was separated into straight line braking with no overlap, get the speed set then take gear and take the turn/ negotiate the hazard.

Speed should still be set before taking the gear and applying steering for the hazard.


plan back>

INFORMATION- SPEED- POSITION-GEAR- ACCELERATION- considered

INFO hazard plan considered (based on conditions and what driver can see etc)


1) Apply straight line braking and get the speed to correct desired, applying clutch when needed.

Position- Make sure you position is correct

Speed
-
2)Once speed is set take the gear and bring clutch up.

Gear
-
3)Apply steering needed now gear and speed are set.

Acceleration
-
4) Once hazard is pasted steering is correct accelerate as per conditions etc


I have not gone into the safety triangle! But that's how to plan back for BGOL!

Edited by DashDriver on Thursday 23 March 14:08