Zen and the art of changing gear.

[Rochester TVR]

R U Local,

I have just read your opening post and I will be putting your words into practice when I next take the sag out for a spin.

My question however is this; Given this scenario what do you do?

Travelling at 60mph on a NSL road and approaching a roundabout. You need to change from 5th to 2nd.

How can you match revs for smooth downchanges when you also need to brake at the same time?

One foot need to be on the clutch, the other on the throttle, but you also need to brake...???

I can change down smoothly when not needing to brake at the same time.

Any advice welcome. (Sorry if this have all ready been covered)

[Robatr0n]

Maybe I had read your post slightly incorrectly, but if I was travelling towards a roundabout at 60mph and wanted to get into second gear I would simply shave off enough speed first by using the brakes, then I would rev match and pop it into 2nd gear at a much more friendly rate of revs but only after I have used the brakes.

[Rochester TVR]

Robatr0n said:

Maybe I had read your post slightly incorrectly, but if I was travelling towards a roundabout at 60mph and wanted to get into second gear I would simply shave off enough speed first by using the brakes, then I would rev match and pop it into 2nd gear at a much more friendly rate of revs but only after I have used the brakes.

Yes thats I what usually do to get the smoothest progress, although it does seem to be the one situation where you have to decide which to do; either brake first and rev match into 2nd at a slower speed, or downchange rev match to let the engine slow you down to a reasonable speed then brake (although I imagine the speed here will be higher than in the first instance)

Using advanced driving techniques is it taught to brakes between downchanges? so you can downchange matching the revs and brakes 'almost' at the same time?

Or is it taught to blip the throttle using your heel while still covering the brakes?

Edited by Rochester TVR on Friday 10th August 14:25

[Robatr0n]

Reg is definatly the best guy to answer the post, but I will still give my input anyway (Stop boo-ing at the back!)

It would completely depend on the roundabout in question, but if it looked fairly clear but an entrance/exit was slightly obscurred from a distance I would brake, change down to second and if the obscurred entrance or exit became clearer as I approached and nobody was about I would continue making progress.

If however I can see a completely empty roundabout with no-body approaching or currently navigating the roundabout I would cover the brakes to knock off some speed and heel and toe into 2nd gear. The reason I would use this method is because I am effectively halfing the distance in which I would normally Brake and then change gear....if that makes sense?

So by doing both heel and toeing I am set up for the roundabout in half the time ready to navigate the empty roundabout.

I would think of it as a little odd and slightly time consuming to rev match and then brake if you are looking to make progress, but I have used this technique plenty of times when coming to a red traffic light just to make good use of the gears and to practice rev matching.

I adapt my style according to situations but often than not I simply brake, rev match, engage gear as its not always effective to make use of heel and toeing.

[R_U_LOCAL]

Rochester TVR said:

R U Local,
I have just read your opening post and I will be putting your words into practice when I next take the sag out for a spin.
My question however is this; Given this scenario what do you do?
Travelling at 60mph on a NSL road and approaching a roundabout. You need to change from 5th to 2nd.
How can you match revs for smooth downchanges when you also need to brake at the same time?
One foot need to be on the clutch, the other on the throttle, but you also need to brake...???
I can change down smoothly when not needing to brake at the same time.
Any advice welcome. (Sorry if this have all ready been covered)

No problem.

I use a systematic approach for roundabouts, seperating the braking and gearchange. So, in your scenario, I'd brake down to 20mph, come off the brakes, and then block change directly into 2nd gear. You could heel-and-toe down through the 'box (part of your right foot braking and part of it operating the throttle), but I find this unecessary on the road.

Rochester TVR said:

Robatr0n said:

Maybe I had read your post slightly incorrectly, but if I was travelling towards a roundabout at 60mph and wanted to get into second gear I would simply shave off enough speed first by using the brakes, then I would rev match and pop it into 2nd gear at a much more friendly rate of revs but only after I have used the brakes.

Yes thats I what usually do to get the smoothest progress, although it does seem to be the one situation where you have to decide which to do; either brake first and rev match into 2nd at a slower speed, or downchange rev match to let the engine slow you down to a reasonable speed then brake (although I imagine the speed here will be higher than in the first instance)

Using advanced driving techniques is it taught to brakes between downchanges? so you can downchange matching the revs and brakes 'almost' at the same time?

Or is it taught to blip the throttle using your heel while still covering the brakes?

Edited by Rochester TVR on Friday 10th August 14:25

I prefer to block-change down the 'box on the road, rather than change down sequentially. Again, sequential downchanges are a preferred option for some on the track, but on the road, I find a single gearchange down to your chosen gear means less fuss, less messing about and less scope for getting things wrong.

[Rochester TVR]

Thanks RUL.

I do try to change down through the box whenever possible, because I feel I am in more control of the engine and weight dristribuation, plus it also saves wear on the brake pads by letting the engine do some of the braking.

Out of curiousity though, do you know how a racing driver would change down the box while needing to brake at the same time?

I guess they would downchange using clutchless gearchanges by matching the revs and left-foot braking at the same time?

Thanks
Lee

Edited by Rochester TVR on Friday 10th August 14:52

[R_U_LOCAL]

Rochester TVR said:

Thanks RUL.

I do try to change down through the box whenever possible, because I feel I am in more control of the engine and weight dristribuation, plus it also saves wear on the brake pads by letting the engine do some of the braking.

Out of curiousity though, do you know how a racing driver would change down the box while needing to brake at the same time?

I guess they would downchange using clutchless gearchanges by matching the revs and left-foot braking at the same time?

Thanks
Lee

Edited by Rochester TVR on Friday 10th August 14:52

There's an old adage in advanced driving which says that it's cheaper to replace your brake pads than your clutch, so if you're changing down sequentially to slow down for mechanically sympathetic reasons, you're probably going arse-about-face. Much better to lose speed through the brakes (it's whet they're designed for, after all) than through engine-braking. Then, once you've lost the speed through braking, just leave yourself enough time for the gearchange.

You could also cause yourself some problems if you get your timing wrong, as by using engine-braking in your TVR, you're only braking the rear wheels, which is a bit like using your handbrake to slow down - you could probably get it right 9 times out of 10, but I wouldn't like to be there for the 10th time!

As for racing drivers, as I mentioned before, in a 3 pedal racing car, the preferred method is to brake hard, and at the same time, use the right side of their rigt foot to blip the throttle.

Have a look at this in-car video of Senna driving an NSX at Suzuka...

http://www.youtube.com/watch?v=A8-zbfdPfRg

Edited by R_U_LOCAL on Friday 10th August 15:11

[The Griffalo]

Rochester TVR said:

Thanks RUL.

I do try to change down through the box whenever possible, because I feel I am in more control of the engine and weight dristribuation, plus it also saves wear on the brake pads by letting the engine do some of the braking.

Out of curiousity though, do you know how a racing driver would change down the box while needing to brake at the same time?

I guess they would downchange using clutchless gearchanges by matching the revs and left-foot braking at the same time?

Thanks
Lee

Edited by Rochester TVR on Friday 10th August 14:52

I used to do this too (coming from a sequential gearbox'd biking background) because I simply didn't believe block changing would be better. I gave it a couple of weeks and it definitely is in a car.

Why? I think it forces you to think further ahead so you arrive at the right speed for the corner every time and also because you have less work to do in the braking zone. One gear change to accomplish rather than three, kinda makes sense when you think about it. It also reduces your braking distance quite considerably.

It does feel alien for a while after sequential changes but now I've perfected it I much prefer it.

[Rochester TVR]

R_U_LOCAL said:

There's an old adage in advanced driving which says that it's cheaper to replace your brake pads than your clutch, so if you're changing down sequentially to slow down for mechanically sympathetic reasons, you're probably going arse-about-face. Much better to lose speed through the brakes (it's whet they're designed for, after all) than through engine-braking. Then, once you've lost the speed through braking, just leave yourself enough time for the gearchange.

You could also cause yourself some problems if you get your timing wrong, as by using engine-braking in your TVR, you're only braking the rear wheels, which is a bit like using your handbrake to slow down - you could probably get it right 9 times out of 10, but I wouldn't like to be there for the 10th time!

I think you have just changed my driving technique in them two paragraphs alone!

Some very good advice.

Thanks
Lee

[ST2]

Mr. Local,

How far from the roundabout would you change into 2nd gear? And would you change into it as a matter of course or would you hold back the gearchange until you have made the decision to go? I do find waiting for vision before decision often difficult and sometimes miss oppurtunities to go that could have been taken had the gear been engaged. RAs with limmited vision are a particularly problem-even slowing to a crawl then taking the gear close to the give way and then a vehicle appears at 12 o'clock from behind bushes on the centre of the RA if then stops to give way to it my vehicle is in lane 1, a prone position and difficult to start off from.

I have read Von,s post on RAs and taking his advice of braking to 30feet before the give way line find I am slowing to early.

I have also read Von's post on brake/gear seperation and again find braking to an "artic's" length also to be too early. I note that for several situations- and i fully understand his reasoning because they happen to me-that he resorts to BGOL. Do you always seperate? And do you always wait until the brake pedal is up before pressing the clutch, or partial overlap by declutching while coming of the brakes and the raising the revs as you come off the clutch?

[vonhosen]

ST2 said:

Mr. Local,

How far from the roundabout would you change into 2nd gear? And would you change into it as a matter of course or would you hold back the gearchange until you have made the decision to go? I do find waiting for vision before decision often difficult and sometimes miss oppurtunities to go that could have been taken had the gear been engaged. RAs with limmited vision are a particularly problem-even slowing to a crawl then taking the gear close to the give way and then a vehicle appears at 12 o'clock from behind bushes on the centre of the RA if then stops to give way to it my vehicle is in lane 1, a prone position and difficult to start off from.

I have read Von,s post on RAs and taking his advice of braking to 30feet before the give way line find I am slowing to early.

I have also read Von's post on brake/gear seperation and again find braking to an "artic's" length also to be too early. I note that for several situations- and i fully understand his reasoning because they happen to me-that he resorts to BGOL. Do you always seperate? And do you always wait until the brake pedal is up before pressing the clutch, or partial overlap by declutching while coming of the brakes and the raising the revs as you come off the clutch?

If it's at a crawl you are approaching are sure you aren't losing too much speed too early ? Obviously I won't know without witnessing what it is you are doing but it sounds like you need to be braking firmer later. Plan it early, but do it firmer later.

If you've got the timing optimal there won't be much spare time, you'll have used it all productively, little wasted. I make up ground quicker on others under braking approaching roundabouts, than under acceleration on the exit side.

Edited by vonhosen on Friday 10th August 16:57

[TripleS]

vonhosen said:

ST2 said:

Mr. Local,

How far from the roundabout would you change into 2nd gear? And would you change into it as a matter of course or would you hold back the gearchange until you have made the decision to go? I do find waiting for vision before decision often difficult and sometimes miss oppurtunities to go that could have been taken had the gear been engaged. RAs with limmited vision are a particularly problem-even slowing to a crawl then taking the gear close to the give way and then a vehicle appears at 12 o'clock from behind bushes on the centre of the RA if then stops to give way to it my vehicle is in lane 1, a prone position and difficult to start off from.

I have read Von,s post on RAs and taking his advice of braking to 30feet before the give way line find I am slowing to early.

I have also read Von's post on brake/gear seperation and again find braking to an "artic's" length also to be too early. I note that for several situations- and i fully understand his reasoning because they happen to me-that he resorts to BGOL. Do you always seperate? And do you always wait until the brake pedal is up before pressing the clutch, or partial overlap by declutching while coming of the brakes and the raising the revs as you come off the clutch?

If it's at a crawl you are approaching are sure you aren't losing too much speed too early ? Obviously I won't know without witnessing what it is you are doing but it sounds like you need to be braking firmer later.

If you've got the timing optimum there won't be much spare time, you'll have used it all productively, none wasted. I do more catching up on others under braking to roundabouts than accelerating away from them.

So sayeth the last of the late brakers?

Actually, unless a fairly high rate of progress is sought, what is wrong with braking fairly early and gently, which is what I normally tend to do, so long as the low rate of speed loss, and the extended period during which it is done, is not taken to the point of causing inconvenience to a following driver?

Best wishes all,
Dave.

[R_U_LOCAL]

ST2 said:

Mr. Local,

How far from the roundabout would you change into 2nd gear? And would you change into it as a matter of course or would you hold back the gearchange until you have made the decision to go? I do find waiting for vision before decision often difficult and sometimes miss oppurtunities to go that could have been taken had the gear been engaged. RAs with limmited vision are a particularly problem-even slowing to a crawl then taking the gear close to the give way and then a vehicle appears at 12 o'clock from behind bushes on the centre of the RA if then stops to give way to it my vehicle is in lane 1, a prone position and difficult to start off from.

I have read Von,s post on RAs and taking his advice of braking to 30feet before the give way line find I am slowing to early.

I have also read Von's post on brake/gear seperation and again find braking to an "artic's" length also to be too early. I note that for several situations- and i fully understand his reasoning because they happen to me-that he resorts to BGOL. Do you always seperate? And do you always wait until the brake pedal is up before pressing the clutch, or partial overlap by declutching while coming of the brakes and the raising the revs as you come off the clutch?

Another oft-used asvanced driving term comes in here. "Planning to stop but looking to go".

I don't like to be too prescriptive about distances etc - I like to have a more flexible approach.

The speed at which you enter a roundabout is dependent on the three "Vs".

The Vehicles on the roundabout
The View on approach and *ahem*
The curVe of the roundabout

So, I'll be planning to stop at the give way markings, but looking for an opportuinity to go. My speed will be dependant on the vehicles, the view and the curve and only once I've got my speed correct and there is a gap to go, will I come off the brakes, select the gear and accelerate onto the roundabout.

[vonhosen]

TripleS said:

vonhosen said:

ST2 said:

Mr. Local,

How far from the roundabout would you change into 2nd gear? And would you change into it as a matter of course or would you hold back the gearchange until you have made the decision to go? I do find waiting for vision before decision often difficult and sometimes miss oppurtunities to go that could have been taken had the gear been engaged. RAs with limmited vision are a particularly problem-even slowing to a crawl then taking the gear close to the give way and then a vehicle appears at 12 o'clock from behind bushes on the centre of the RA if then stops to give way to it my vehicle is in lane 1, a prone position and difficult to start off from.

I have read Von,s post on RAs and taking his advice of braking to 30feet before the give way line find I am slowing to early.

I have also read Von's post on brake/gear seperation and again find braking to an "artic's" length also to be too early. I note that for several situations- and i fully understand his reasoning because they happen to me-that he resorts to BGOL. Do you always seperate? And do you always wait until the brake pedal is up before pressing the clutch, or partial overlap by declutching while coming of the brakes and the raising the revs as you come off the clutch?

If it's at a crawl you are approaching are sure you aren't losing too much speed too early ? Obviously I won't know without witnessing what it is you are doing but it sounds like you need to be braking firmer later.

If you've got the timing optimum there won't be much spare time, you'll have used it all productively, none wasted. I do more catching up on others under braking to roundabouts than accelerating away from them.

So sayeth the last of the late brakers?

Actually, unless a fairly high rate of progress is sought, what is wrong with braking fairly early and gently, which is what I normally tend to do, so long as the low rate of speed loss, and the extended period during which it is done, is not taken to the point of causing inconvenience to a following driver?

Best wishes all,
Dave.

I don't think you prescribe to brake gear separation or waiting to take the gear until you know if you can go though Dave (which is what ST2 appears to want to do). The firmer later braking will help in achieving those aims.

You can use whatever method you like or works for you, but my advice is geared towards someone wanting to do it incorporating those methods or goals.

[GreenV8S]

R_U_LOCAL said:

As you can see, the engine is held at 4000 RPM, which allows you to time your clutch release much more easily and accurately - the time available for releasing the clutch at 3 is much longer.

I don't think you have mentioned the other benefit, that the sustained revs approach means you have the throttle established at a neutral torque so that by default nothing much changes after you engage the clutch.

If you are blipping the throttle to match revs then the revs might be right as the clutch engaged but you will find the revs try to carry on climbing or dropping so you get engine braking / acceleration straight away.

[instructormike]

My two-penneth....
AS RUL says, braking for a roundabout is done for the following reasons; to be able to negotiate the roundabout itself; to reduce speed for the stop until observations indicate an ability to go. One's plan should always be to brake progressively to stop just before the line, until your observations say that you can go. Obviously, with a clear vision one can time one's arrival (acceleration sense etc.) so that it coincides with the "gap" behind the last car you are waiting to clear. However, by braking late and harder in a more closed vision roundabout one buys oneself more time at low speed to ascertain the ability to go. Early braking, apart from the TakeUSeGive aspect of warning fellow drivers of an impending hazard, serves little purpose if it does not aid decision-making for the roundabout. "Slow until you can go, when it's clear take THE RIGHT gear" not two or three on the way in, is what I can hear myself saying to my "students". Why take second gear when you end up taking first, for example? Also, subconsciously, taking a gear leads the driver towards a going-through mentality anyway. On road all gear choices should intrinsically be to accelerate anyway and should therefore be linked to an observation that says that an increase in speed is OK.
Sequential downchanging is definitely suggesting a less considered and more race-type approach, as has been said, and not exactly appropriate for the road. It might sound good in a 360 (it does), but the old dear on the zimmer probably doesn't share your opinions. Again, blipping suits faster changes rather than the controlled selection of the one correct gear.

Edited by instructormike on Friday 10th August 17:36

Edited by instructormike on Friday 10th August 17:46

[vonhosen]

ST2

I'll try to explain with a rather crude quickly drawn diagram (remember there are a lot of variables so this is a simplification).




As R_U_LOCAL says, the plan is to stop at the give way, but you are looking to go if it's clear for you to.

You want to be making progress to the give way line but be able to stop smoothly at the give way (should you need to) incorporating 3 stage braking.

In order to be able to combine progress to & stop at the give way smoothly, you would finish 2nd stage brakes a short distance back from the give way & then use 3rd stage brakes to ease up to the line.
It is at around the time you finish the 2nd stage brakes that you will be able to decide if you can go or not (depending on vision right). If you can't you are setting your steering for the desired line into the roundabout & easing into 3rd stage brakes to stop at the give way (obviously dipping the clutch and getting first gear).

If it is safe for you to go, you finish setting the steering for entry & AFTER doing that, you come off the brake, hold the steering wheel with a high right hand & take the gear with the left. If you've got the pace right you'll be able to get an unrushed gear, have the clutch up & be back to the throttle at the latest prior to the second green line. You can then pull steering on with the high right hand to negotiate the curve right. The earlier you are set up for entry into the roundabout by setting the steering, have the speed right to negotiate it safely & have the vision right to know you can get in safely, the earlier you can get the gear.

If you don't carry some speed to the first green line you'll have little inertia to take any gap available briskly when you come off the brake.

The Stressed one posted a video a while back showing a bit of straightlining in roundabouts, although you can't see the lateral vision that's clear to go, you can get a feel for the firmer later braking & you can hear the rev for the gearchange to establish when it's done in some (although you'll notice he is going down through the box on some, but the purpose for you is the illustration of carrying some speed to the roundabout.)
Here's the link he posted.
http://www.hpc.org.uk/mkrb.wmv

Edited by vonhosen on Friday 10th August 18:15

[GreenV8S]

Playing devil's advocate for a moment, what's your position on coasting either with the clutch down and/or out of gear, while approaching a hazard? There's a follow-on question that you can probably guess, but I won't ask it yet because I don't want to presuppose your answer.

ETA: this was really a response to instructormike's post, not Vonhosen's.

Edited by GreenV8S on Friday 10th August 18:05

[TripleS]

vonhosen said:

TripleS said:

vonhosen said:

If you've got the timing optimum there won't be much spare time, you'll have used it all productively, none wasted. I do more catching up on others under braking to roundabouts than accelerating away from them.

So sayeth the last of the late brakers?

Actually, unless a fairly high rate of progress is sought, what is wrong with braking fairly early and gently, which is what I normally tend to do, so long as the low rate of speed loss, and the extended period during which it is done, is not taken to the point of causing inconvenience to a following driver?

Best wishes all,
Dave.

I don't think you prescribe to brake gear separation or waiting to take the gear until you know if you can go though Dave (which is what ST2 appears to want to do). The firmer later braking will help in achieving those aims.

You can use whatever method you like or works for you, but my advice is geared towards someone wanting to do it incorporating those methods or goals.

Hiya, Von - I was merely commenting in relation to the intensity of braking - in your case typically fairly late and quite firmly - as opposed to my normal style of early and gently, thus taking more time and a longer distance over it, which means I sacrifice some progress of course. I wasn't thinking about the timing of gear changes and their relationship to the braking.

Best wishes all,
Dave.

[R_U_LOCAL]

GreenV8S said:

Playing devil's advocate for a moment, what's your position on coasting either with the clutch down and/or out of gear, while approaching a hazard? There's a follow-on question that you can probably guess, but I won't ask it yet because I don't want to presuppose your answer.

ETA: this was really a response to instructormike's post, not Vonhosen's.

Edited by GreenV8S on Friday 10th August 18:05

I'm anticipating a "what happens if the revs drop to the point where the engine starts to judder?" question - am I right?

The braking should be dome in the higher gear right down until the engine revs approach tick-over speed in that gear. Once you've reached that speed, then you should dip the clutch to prevent judder. This is different from coasting in the accepted sense, which is more a case of dipping the clutch as soon as you start to brake, or even putting the car in neutral whilst braking.

Even in top gear, you'll be down to 10-15mph before you have to dip the clutch, so the distance travelled with the clutch down is generally only a few yards.