Or if the clutch cable had failed you could carefully match the revs and get away with it.
I drove my 61 Beetle from Lewes to Brighton with no clutch cable - put it in first gear with the engine off, then held the starter in until the car had attained walking speed and the engine had fired up. Then carefully matched the engine revs up and down the box.
Ian
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I'm missing something..
I can see the rev matching and therefore using the clutch & throttle together - but where did the brake get involved ?
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Ah...glad you spotted that, Mark. The whole purpose of the plot was, I think, to be doing this down shifting as part of the braking exercise before entering a bend. Then you ended up in the right gear to power away and didn't waste time braking THEN changing gear.
Or so my memory tells me.
Ian
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Having always been a bit of a stiffy, I only ever really got it right with a centre throttle. With a Lagonda Z-type box (no lamp-swinging, a high-chassis 3-litre special was only an old car when I had it) you had to get it RIGHT.
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The point is, this is the only way to drive a manual car fast. For example, if one approaches a corner in fifth gear, but wishes to power out of the corner in third, the driver must change down. If you brake hard into the corner, with the tyres slipping around 7-10% (attempting thresshold braking) you must change gear very smoothly, otherwise the additional braking effect will cause the tyres to slip too much , or in the worst case scenario, lock up. You must be in the right gear when you turn into the corner. Hence the need to blip the throttle with the side of your foot whilst braking to achieve a smooth gearchange. Alternatively, Scandiavian rally drivers pioneered a technique of braking with there left feet. Unless you are a very skilled driver this is probably only sensisble in a car with a "dog-legg" gearbox.
Ben
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Ben made his post whilst I was typing so I might as well comment on the left foot braking technique.
Can't recall whether this was pioneered by Eric Carlsson in the 2 stroke Saabs in which the free wheel device made it easy, but I think the first driver to use it reliably with a normal manual box was Timo Makinen, (Tommi's Dad) in the works Cooper S. In fact I recall an old rally film comparing Timo's technique with the conventional one of Hannu Mikkola in the works Escort Twin Cam in practice for the Thousand Lakes late 60's.
In those days the gear changing was not easy in connection with left foot braking, and I never mastered it, but in today's cars with the sequential gearbox, almost the only time you use the clutch pedal is to get off the start line.
You must remember that these cars have split circuit brake systems, with separate circuits for front and rear brakes. Each circuit has a different master cylinder connected by a sort of balance arrangement so you can adjust all the braking effort forwards or backwards dependant upon the surface and road type. The real guys, adjust it on the fly mid stage.
The significance of this is that you can put so much effort on the rear wheels that when you brake you get the effect of pulling on the handbrake but in a much more controlled way so that the back of the car steps out of line and is then in a much safer position to deal with a bend which might tighten. All this is of course techniques for loose surfaces and non public roads, honest occifer. So if you use the left foot to hit the brake you can keep the right welly on the gas, or should it be the right slipper?
Most cars have so much braking effort on the front wheels that its impossible to emulate this with the standard set up.
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Taken some time to get to this thread, been working away and then at the outlaws.
Interesting drive last week in **extremely** slippery conditions which I will put in another thread when I get round to it. Bit topical considering weather you got in UK last week.
I assume David W was referring to me for chapter and verse on this. If not sorry for being presumptious.
Most of you have already covered the chapter and verse but here's my bit to explain where braking comes in.
John Slaughter was spot on in his description of technique in covering brake with ball of right foot and "blipping" throttle with outside of right foot to match revs to gear speed.
Apart from the no synchro bit nowadays its really a competition technique to enable braking at the last second and yet be in the correct gear as early as possible so there is no time lost spent freewheeling during the change. Right, so that technique, as written, probably does not have much place on the public highway, by that I probably mean being the last of the late brakers, however much fun it is.
For ages its always been recommended that braking and gear changing should not be done together, ie approach hazard, brake to desired speed, change into desired gear, then go. (i've missed out all the mirror checking and so on)
Its now accepted, I believe also by the IAM and police, but I could stand correcting there that there are certain circumstances when overlapping braking and gear changing is an acceptable and even desirable technique.
Let us imagine going down a steepish hill and intending to take a turning to the left.
IN the previous system,
you braked to the speed,
stopped braking,
changed gear,
then the vehicle had speeded up again due to gravity so sometimes you had to brake again.
Alternatively if you were perfect you would slow a bit more to allow for the bit of increase in speed during the gear change. All this takes up more time and road, during which the rep in the Laguna up your rear end is getting closer and closer, if that were possible.
So if you want to brake and change gear at the same time the simple way is to keep on the brakes, whack the gear change through on the synchromesh during braking and use the clutch to drag the engine revs back up, not very smooth and if the change/clutch action is a bit harsh it unsettles the car and can even unstick the rear wheels in a rwd car. (also colloquially known as diff braking technique, and braking in this case is too often spelt breaking!)
So what you do is towards the end of the braking period, you keep the pressure on the brake, and change gear in one go, say 4 to 2, matching engine revs to keep the drive smooth and the car stable. To do this you need to overlap your foot on both brake and gas per the John S description.
The best way I can put this is to quote verbatim from Roadcraft. HMSO publications, worthwhile read IMHO.
"Sometimes it is helpful to overlap braking with the gear change. Do this by braking normally and changing gear towards the end of braking. The advantages of this are that it takes less time, contributes to vehicle stability and is often safer because your progress matches the expectations of other road users.
These disadvantages have to be weighed against the disadvantage that for part of the braking period both hands are not on the steering wheel, and the possibility that the technique could lead to late, excessive braking and rushed gear changes."
The section then goes onto how this should be included in your planning.
Hope thats clear, and I've not repeated myself too much.
Just as an add on I got stressed during the writing of this post because I realised IF I TYPED BARKING INSTEAD OF BRAKING ONE MORE TIME I WILL SCREAM its one of those words I always get wrong)
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Other variants on non-standard foorwear are a) gumboots b) barefeet
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Wots wrong in driving in your bare feet.? My wife drives her auto with her right foot bare..
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