Cos yet again yesterday I observed the Octavia holding D1 until some headway was gained, this when pulling away, and spinning a little, on a snow covered surface, not instantly snicking into second as she would normally do.

Therefore my comment about minimising the differential in wheel rim speed against forward speed appears to be correct.

i.e start in first if it is slippery.

cheers

M

Darn it that was supposed to read "me & the VW..........................

Edited 3 December, 201015 yr by dieseldogg

Just because your auto chooses to hold 1st doesn't mean its the best way for gaining or maintaining traction in the snow :wonder:

The reason that its best to start in second gear on a slippery surface is that torque at the wheels is reduced in 2nd and therefore you are less likely to overcome the reduced friction between tyre and road surface - i.e. you less likely to spin the wheels. This is not a matter of opinion, its basic physics. Most autos have a 'winter' setting which locks out first gear - the DSG doesn't.

Sorry, i may be appearing a bit "dreagh" but surely if in second the wheels MUST be turning faster, therefore unless the car can accelerate, ( and it cant cos its slippery) it is more likely to break traction, unless slipping the clutch to reduce the rim speed/road speed differential.

But if slipping the clutch? .....................do it in first, as it would be more mechanically sympathetic.

And unless I have missed something one can limit the torque with proper clutch control, like for example when waiting on a slight uphill slope, hold the car on the clutch, to amuse oneself let her run back a tad, effortlessly bring her back to a halt and move back forward again, all without touching the brake.

Simples.

i.e. Torque should not be/ is not a problem with proper clutch control.

And since the 7 speed DSG surely represents the distillation of umpteen years knowledge & experience, it must? be configured for optimum traction,

I dont know whether the ESP package talks to the DSG or how it works, but it does work that way.

Cheers

M

I should add that I have occassionally "recovered" vehicles ( & a 7.5tonne lorry) that others assured me were "stuck".

They werent.

I drove them out, without assistence.

Its all to do with first reading the road/situation/terrain/conditions and then working with these as far as possible.

Not "fighting" them, as is sometimes the incorrectly chosen course of action, albeit perhaps in the "heat of the moment"

No abuse of the vehicle or its compenents is necessary either.

***************************

Note to self: Must wear sunglasses when polishing Halo

Edited 3 December, 201015 yr by dieseldogg

Well I don't agree with this, starting in second with sympathetic clutch control makes it harder to spin the wheels. And as stated most manufacturers have a winter setting on their autos that starts the car in second for this reason. But if you're happy in first with your DSG (not that you have a choice) then knock yourself out.

I've been starting in first and/or second and it has been fine every time, no throttle and gentle clutch action has worked fine.

Who's "mw"?

The reason that its best to start in second gear on a slippery surface is that torque at the wheels is reduced in 2nd and therefore you are less likely to overcome the reduced friction between tyre and road surface - i.e. you less likely to spin the wheels. This is not a matter of opinion, its basic physics. Most autos have a 'winter' setting which locks out first gear - the DSG doesn't.

+1

On some cars with TCS you can clearly see it is the case. When trying to move off in first, the TCS is so invasive you will barely move (if at all). In second, the TCS intervenes less frequently and you can get going.

Come on, this is basic GCSE physics. The fact that 2nd gear has is a higher ratio than first and the 'wheels spin faster' is irrelevant, Once the wheels are spinning the battle is lost, no matter what gear you are in. The object is to avoid breaking traction at all. To that end you need to reduce torque to the driven wheels, so use a higher gear (i.e. second). There is much less torque in second gear, so it is more difficult to spin the wheels. Gear ratios generally follow geometric progression, so second will give you typically 30-50% less torque than first and consequently a slip-free pull-away is easier to achieve.

Edited 3 December, 201015 yr by Hauptmann

Hauptmann,

Dur!, (to misquote our 18 year old) I do understand the inverse relationship between gear ratio & torque at the road wheels.

Cept how is it relevent, as one is/should be controlling the torque with the clutch, as what other element can one control with the clutch?

A clutch transmits torque, and hence with revolutions transmits power, but as I understand it first & foremost a clutch is a way of controlling/limiting torque.

PS

I managed to start a Hillman Hunter from rest in 3rd gear ( & her only had 4 gears) during my driving test, which I passed on that, my first attempt, the examiner asked me did I know what gear I had been in, I said third, Hmmmmmmmmmmmmmmm, he said, nicely done and he let it go.

PPS

The missis is an astrophysist, and a crap driver (as she will be the first to admit, cos to her it is merely a necessary evil)

Cheers (chus?)

M

PS

I have never questioned the reduction in torque in higher gears, merely question this skewed (imho) application thereof.

Edited 3 December, 201015 yr by dieseldogg

Question is that now we seem to be experiencing 'REAL' winters again how long before one of the DSG remapping companies realises that that there is a market for a 'winter' setting remap pfor the DSG box ......

Skud,

I would understand that the Checkz republic and Germany et al, generally already experience "real winters", therefore the DSG as is, is perfectably well configured to gain traction in poor conditions.

But hey VW probably dont employ the best engineers or designers.

Just a thought

M

sigh

but then there them as think that aftermarket snake oil magnets will improve performance, save fuel AND improve ones sex life.

Edited 3 December, 201015 yr by dieseldogg

Skud,

I would understand that the Checkz republic and Germany et al, generally already experience "real winters", therefore the DSG as is, is perfectably well configured to gain traction in poor conditions.

But hey VW probably dont employ the best engineers or designers.

Just a thought

M

sigh

but then there them as think that aftermarket snake oil magnets will improve performance, save fuel AND improve ones sex life.

another way to look it at, is that your only driving around in a 1.6CR octavia. thats a low power engine in a heavy car, therefore you wont have to much of an issue with the wheels wanting to spin up easy.

Much more difficult when your running 280hp. As a comparison, even a stock TFSI vRS is making more power than your 1.6CR by around 2600rpm. So whilst your car is happy to do it in 1st, others wouldnt and is exactly the reason for putting it into 2nd gear

Edited 3 December, 201015 yr by janner_Sy

What the heck does it matter what blummin gear yer in as long as ye get going....

No, I haven't been stuck....yet.

the horsepower should not matter, its the application of the horsepower (er ............by the driver) that causes problems.

I should probably enjoy a "go" in a high powered car, might have to refine my technique a little but hey ho that life.

I suspect that with the high powered car goes low profile tyres again this will cause problems in the snow.

And despite my heavy low powered car I was gently spinning when attempting to start on the up-with outside Muhollands parts counter this morning, I really should have parked facing downhill.

In second I would merely have spun faster.

I should really have nicked her into second and braced my self for some sort of launch control effect, as promulgated in various posts as above.

But I was not sure that i would be able to cope with the resultant acceleration .

You won't be convinced that second gear often makes setting off in snow easier, not in this thread or your other one.

Let this thread die, please!

The object is to avoid breaking traction at all.

Yes.

To that end you need to reduce torque to the driven wheels, so use a higher gear (i.e. second).

I can't agree.

There's a given amount of torque you'll need to apply to move the car, and a given amount of torque you *can* apply before the wheels spin. So long as the second exceeds the first, the car will move, regardless of the gearing between the engine and the wheels, and if it's the other way round the wheels will spin. All that starting in second does is make up for clumsy application of the torque.

In second I would merely have spun faster.

No, in second the reduced torque AT THE WHEELS would mean that you could have moved away without spinning the wheels at all. And not spinning the wheels at all is the optimum technique for moving off no matter what the road conditions.

You're correct to an extent what you say about modulating the torque getting to the wheels with the clutch, but the fact is that this is much easier to do if you are in second gear as the level of torque getting to the wheels (for a given clutch engagement) is reduced. Therefore you will have to slip the clutch less to avoid the wheels spinning, and thus starting in second is more mechanically sympathetic.

You won't be convinced that second gear often makes setting off in snow easier, not in this thread or your other one.

Let this thread die, please!

I'm inclined to agree (even though I've just kept it going!)

Some drivers can drive. Some cannot. Never mind the physics and the torque.

Some drivers can drive. Some cannot. Never mind the physics and the torque.

That's very true, but I always think if people thought about the physics more (i.e: what happens when they use the car controls) they'd cope better. The number of times you see posts from people who hit the brakes on a slippy surface, and wonder what the rattling noise and failure to stop is....

CJB.

Spot on. That was my point too!

First gear and no accelerator,(unless on an ascent) decent clutch control, if the car doesn't move then it never will. Setting off in second will just burn your clutch out quicker as you increase the revs to avoid stalling due to the lack of torque. The idea is then to get it into second gear as soon as possible, ie as soon as the car is rolling, to increase speed without using the accelerator, once in second gear you can gently apply the accelerator to further increase speed with a reduced risk of spinning the wheels.

Edited 4 December, 201015 yr by postmanpat

Makes you kind of despair when you read some of the replies in this thread.

If you look at the answer I posted earlier you'll see that I didn't say that starting in 2nd gear would eliminate the chances of wheelspin, it simply makes it EASIER to pull off and accelerate without wheel slip. Its just a method for reducing torque to the driven wheels and reducing throttle sensitivity. The latter part is important because modern 'fly by wire' throttles can have a pretty non-linear response on initial movement.

I have a remapped vRS TFSI and starting gently in second is a little easier than first on snow and ice. The revs are so low that I don't think clutch wear is a consideration.

Anyway, I'll say no more on this well-proven technique.

Makes you kind of despair when you read some of the replies in this thread.

. The revs are so low that I don't think clutch wear is a consideration.

Anyway, I'll say no more on this well-proven technique.

Sorry but also basic gcse physics state that for a given rpm in 2nd gear the wheels will be rotating faster than they will be in first.

Also because there is less torque you will need to slip the clutch and use higher revs to set off in second to avoid stalling.(which is also a misnomer as the engine will provide the same torque at a given rpm regardless of gear it just won't be enough in higher gears to pull the weight from a standing start, hence the need to slip the clutch)

Setting off in second with high revs is fine for little old ladies who have no idea how to drive and have no clutch control, the wheels are less likely to spin (the same could be said for 3rd and 4th for that matter) and because they are depressing the accelerator they are less likely to stall.

You can despair all you want to but talking as someone who has to stop (and set off again) every couple of hundred yards, regardless of terrain and on un-swept side roads, and who hasn't got stuck once or melted the clutch in the last week then I will stick with my method.

Edited 4 December, 201015 yr by postmanpat

cjb

kevberlin

postmanpat

May I suggest we form some sort of an affiliation to spread the gospel of proper snow driving. tee hee

You have each expressed what I was trying to explain, & probably more clearly & definately more succiently (to self)

I have experienced the same at work during the past twenty years regarding a persistent myth:

i.e. "One MUST have a 4*4 to tow a twin axle trailer, its the law" , Plated weights? pagh! never let facts interfere with a good argument!!

I simply keep asking "show me" where this is written down, they cant , but passionately believe it to be true nonetheless.

As the Yorkshire man was supposed to have said "theres nowt so strange as folk"

Good night ( for now )

Did I mention, like Arnie.... I'll be BACK :p

Edited 4 December, 201015 yr by dieseldogg