double-declutching- how to - in a specific situation

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Offline Bjornung

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Recent postings related to double-declutching prompted me to seek advice from the forum.
I could not find any tips about this searching the forum. This is mostly related to proper operator practice.
I manage to double de-clutch fine in most situations, but one particular situation always makes me struggle:

Typically, for instance, coming towards a roundabout in 3. gear, slowing down and and needing to use the brake to yield for traffic in the roundabout.
As the speeds slow down to the point where a downshift into 2. might be necessary, depending on traffic - I find myself with the right foot on the brake, left foot is used to de-clutch, but as I still need to slow down using the brake - how do I blip the throttle before getting into 2.?
Or is there another way of doing it?
I never seem to mange this properly, especially as typically the situation needs very quick reaction in order to follow the flow in todays fast moving traffic.

Bjørnung

Offline fifty seven

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Contrary to things modern driving instructors and examiners will tell you today, a classic brake system is not the only way or most trustworthy method to slow a classic vehicle down. Brake linings which could wear out, might need adjustment and 'fade' if used too hard for too long, or might be wet !!!  were always the second best alternative to using the gearbox, and engine braking. Lorries are still fitted with engine retarders for this very reason...a second "back up" system to save the brakes.

All that said,  I feel you should never get into a situation where you are needing to do so many things all at one. My driving instructor course  ( Army ) emphasised " predictive" motoring. This included realising which gear would be required for what was to occur along the road ahead before you got there. Not going through a city street in top gear, changing down before a climb, being prepared to stop if a bend went into a blind spot, and so on.

So, on approach to your roundabout you will change down into third. . As you look to drop in ...as with a  "zip" fastener ... to join into traffic on the junction  you should see whether third will be adequate to adopt the speed they are at, or second gear will be better.
Only practice will let you know the noise of the Land Rover engine at each speed. But when you do learn this you will hear the exact moment to shove the free spinning shaft into gear, and then release the clutch again.

A small throttle "blip" allows the free spinning shafts to accelerate so the gear teeth are going fast enough to catch the new unsynchroed gear. Once you know this engine note at each speed for each gear, double clutching is no longer really needed at all.   You have one chance at this gear change if you approach a busy roundabout far too fast. The selection should not be left so late, so near to the "crisis point" , until everything happens at once.
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Online GunnarTM

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When learning to drive old sports cars, one was taught to "heel-toe" https://en.m.wikipedia.org/wiki/Heel-and-toe_shifting , which in the standard pedal layouts that emerged actually evolved into using the front of one's right foot for the brake and gas pedal simultaneously.  However, the size and height of the Series accelerator pedal makes this tough to do, so instead of using my big toe on the brake, I use the ball of my foot, which allows me to lightly blip the gas with the right (small toe) side of my foot.

Fun fact, I had some uncles who were race car drivers, and they used to cut the bows off of old opera pumps https://en.wikipedia.org/wiki/Court_shoe in order to obtain improved pedal feedback through the thin leather soles.  I usually drive the Series in a pair of lightweight hiking shoes, and find they provide feedback aplenty ;-)

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Online GunnarTM

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P.S.  High-performance race driving in a Series is contraindicated!  This appears to have been taken at the Nurburgring.

Source: https://www.facebook.com/GreenlandWorkshop/posts/3800885846626503

Offline steven poultney

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Well Gunner that photograph made me laugh aloud so thank you for that, it made me think of the regimental motto of one of the regiments I served with the 17/21st Lancers, "Death or Glory", never mind what the instructor said!  Late 60's early 70's I'd say, just my era.
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Offline scimart

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  • Location: Bedfordshire, UK
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All the double de-clutching practice came in handy the day the weld on the clutch operating clutch shaft failed as I left work one evening.  As I rarely used the clutch on my work Bedford HA (Viva) van during the day for anything other than pulling away and stopping, the trip home in the S1 through rush hour traffic was relatively easy and the nice low first gear ratio made the required "in gear" starts pretty much drama free.

Offline Bjornung

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  • Location: near Stavanger, Norway
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Many thanks to all who commented.
To fifty seven - I should have mentioned that most roundabouts here in Norway are very small - some very very small diameter.
Still - normally I do go through roundabouts in 3. ...so the situation described was more like that I plan and hope to be able to through in 3. while slowing down on the 3. gear, but have to be prepared to brake and then somehow be able to shift smoothly down into 2. if something unexpected happens (other traffic) ....and that's where I sometimes have problems.

Well - practice and practice is needed I suppose. :-)

Bjørnung

Online GunnarTM

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Agreed, late '60s/early '70s ... I don't think they let people sit on the guardrails anymore. Looks like an LHD BAOR truck 69ER37 in service!

Offline fifty seven

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Bjornung ..(Yes roundabouts are small and my son who is now there every week must drive across many of them ! )

To add to things Scimart has said.  It is useful to think about  How to change gear without the clutch at all.

A clutch is a necessity for starting and perhaps for coming to a halt( perhaps) but once rolling along it can be a luxury, hardly needed.

Careful balance of application of power via engine revs can release the forces on each gear by dropping engine revs so it is possible to knock the gear free. ( Note the word knock is used here)

The same careful balance of engine revs can be used to knock the next gear into position.

Another thing I was taught never to do with a truck or Land Rover gearlever is to grip it firmly.  Use only the palm of your hand. To get gear 1 and 2 the hand should be over to the right of the gear lever. The heel of the hand  "knocks" the lever forward into gear one, the fingers are used to  knock back into gear two, then to get gear 3 move the hand across the lever head so the whole hand is to the left of the knob.  Again use heel of hand to knock the lever forwards to get to 3rd,  and next with only fingers applied, to knock the gearlever back into 4th.

The base message..it is unnecessary to actually grip the lever tightly at all.  Doing this will ensure the lever cannot be used to force a gear to engage when it would not do so easily and smoothly.

Take your self to a deserted road and try this once on the move and without using clutch at all, using engine revs alone. It will be informative , unless of course my son is coming the other way  :hmm:

Offline Willerby

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  • Location: Norfolk, UK
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I used to struggle with this then I slowed earlier and harder, effectively changing into second and trundling (even accelerating slightly) to the roundabout rather than trying to move into second too close and too fast.

As we say here, ‘SLOW YOU DOWN’

Offline Trakgrip

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...
I find myself with the right foot on the brake, left foot is used to de-clutch, but as I still need to slow down using the brake - how do I blip the throttle before getting into 2.?
Or is there another way of doing it?
...

Two choices really, either heel-and-toe or plan your decelleration so that you can come off the brakes, double-declutch down a gear, and then resume braking. The latter is what I do by force of habit in my TDCi Defender, since the pedal arrangements make heel-and-toe changes impossible.

Learning to drive a manual transmission without using the clutch at all is a (very occasionally) useful skill. I taught myself to do this driving mainly non-synchro gearboxes not long after passing my test, and on at least two occasions it has allowed me to drive significant distances home after suffering a complete failure of the clutch (once in a SAAB 99 and once in my 86" S1). If you have a no clutch at all you have to start the engine wit the car in gear, and it certainly teaches you to think ahead to try to avoid altogether having to stop.

As a general trend, ever since the motor vehicle was invented the task of driving it has been progressively de-skilled and this has resulted in the skill of those who do progressively diminishing. One manifestation of this is the incredibly small number of younger people who know how to double-declutch, but unless you are an enthusiast why now would anyone bother to learn how to do something they'll never need to do?

Straying somewhat from the OP's question, my concern is that this trend has gone too far, and modern cars now turn on  the lights, turn on the wipers, park themselves, brake and/or steer in an emergency, and before long will "intelligently" limit their maximum speed. As you make a task easier, more inept people think that they are capable of undertaking it.  We are already seeing drivers who are too clueless to turn on the correct lights for the conditions, where will it end? I have a lot of sympathy with the school of thought which says that fitting a sharp spike instead of a driver's airbag would almost immediately make the roads much safer. 
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Offline scimart

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  • Location: Bedfordshire, UK
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I find myself with the right foot on the brake, left foot is used to de-clutch, but as I still need to slow down using the brake - how do I blip the throttle before getting into 2.?
Or is there another way of doing it?

Bjørnung

Perhaps my lower leg structure differs but I’ve always managed to swivel my right foot such that my heel can blip the throttle pedal - not just on my S1 but other vehicles and wearing anything from trainers to wellies.



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Offline Bjornung

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Again thanks for all comments and advice,
I have some new methods to try out!  :D

Bjørnung

Offline Trakgrip

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  • Location: Dorset
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Perhaps my lower leg structure differs but I’ve always managed to swivel my right foot such that my heel can blip the throttle pedal - not just on my S1 but other vehicles and wearing anything from trainers to wellies.


Indeed, the same for me. I do find that modern vehicles tend to be harder (and some impossible) and I suspect that back in the pre-synchro era the pedal layout was designed to allow heel-and-toeing. Nowadays I don't suppose that the designers of vehicle have a clue what it involves, and certainly won't give it a thought when laying out the controls. Can you imagine Gerry McGovern double-declutching?

 

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