Mega Winter Tyres thread, all questions here!!

turbodiesel

Confab wrote: »

Anyone know of anyone in Dublin (ideally the north side) that does partworn winters?

Have a look on donedeal.

I think i've seen glasnevin/finglas/blanch mentioned.

PauloMN

Confab wrote: »

Anyone know of anyone in Dublin (ideally the north side) that does partworn winters?

http://www.tyreland.ie/ is where I got mine, Glasnevin. They also have a place in Swords according to their website.

Never had winters so can't comment on them performance-wise until it gets cold, but they've at least 6mm of thread left (two of them look almost new), so they seem like a good deal, and they all seem to be premium brand ex-German tyres.

No1J

Confab wrote: »

Anyone know of anyone in Dublin (ideally the north side) that does partworn winters?

Tyreland glasnevin quoted me for 195 65 15 low wear 6mm left, (class A) €48 each, major brands, fitting extra (€40).


Went for the new ones with steel wheels, I should get about 5 years out of the 2 sets of tyres, at least.
5 years of changing summer/winter back and forwards would cost €400 not to mention the inconvenience, wear and tare/ damage.
Actually no harm to have a hands on look at how your tyres are each change.

MagicMarker

Is there anywhere other than camskill online? I checked and there's no winter stock in the size I need.

I realise this has probably already been answered 10 times over but it's a long thread!!!

Anan1

MagicMarker wrote: »

Is there anywhere other than camskill online? I checked and there's no winter stock in the size I need.

I realise this has probably already been answered 10 times over but it's a long thread!!!

Try eiretyres and pneus online.

JJJJNR

Retreaded tyres are only for trucks I thought.. ?

-Corkie-

JJJJNR wrote: »

Retreaded tyres are only for trucks I thought.. ?

Re anything with tyres is a waste of time imo. I havent heard of retreads for cars in years but as you said they are commonly available for trucks..

PauloMN

-Corkie- wrote: »

Re anything with tyres is a waste of time imo. I havent heard of retreads for cars in years but as you said they are commonly available for trucks..

'Scuse the ignorance, but are retreads=remoulds or are they something different?

-Corkie-

PauloMN wrote: »

'Scuse the ignorance, but are retreads=remoulds or are they something different?

No same thing.

cjmcork

the tyres I bought a month ago have gone up 7 quid each on Eiretyres............eeek! buy now people!

islanderre

Fitted two Hankook Winter Tyres yesterday; €180 total fitted. Top two photos. Bottom photo is the Uniroyal tyre I took off; great tyre too.

Will fit the two part worn (Firestone) @ the end of the month....... used these last year and was very impressed so spashed out on two new tyres this year.

Should help me stay tween the ditchs.

Kategill

Don't know about rotating summer tyres will it help with snow...but do know that all manufacturers recommend that all new tyres are fitted to the rear od the car.... the reason for this being the weight of the engine assists the grip on the front of the car, the extra thread on the back avoids the back end losing grip.... different if its a rear engine car of course...

spank_inferno

For those with Haldex all wheel drive systems.

If the cost of purchasing winters seems excessive, would it be sensible to purchase 2 winters for just the front wheels?

Seeing as most of the torque goes to the front, this would be ok wouldnt it?
Or would it work against the car if some torque is going to the rear?


many thanks

Matt Simis

spank_inferno wrote: »

For those with Haldex all wheel drive systems.
If the cost of purchasing winters seems excessive, would it be sensible to purchase 2 winters for just the front wheels?
Seeing as most of the torque goes to the front, this would be ok wouldnt it?
many thanks

"Just 2" winter tyres on a car has been asked before and generally no, its not a good idea. Oddly you pick out Haldex quattro.. if anything its even worse than FWD for the 2+2 setup!

The way I see it: In a FWD car the front wheels with Winters will generally allow traction, dead straight braking (dont try on a brake on a corner with unbalanced tyre setup). When front slip occurs the driver feels it and adjusts, as does ESP by bringing on situational brakes (which will not all exert diff brake power thanks to tyres diff, so not great).


However on Haldex it will first try to regain traction lost on Winter enabled front wheels by increasing power to the rears. Those rears have summer tyres on, meaning when the power goes to them they will quite rapidly loose traction and spin. Forcing ESP on in a big way to brake those wheels leading to all sorts of weird behaviour.

Haldex assumes you have similar tyre/brake performance all round, putting Winters on one axle completely screws that logic over.

BostonB

Kategill wrote: »

Don't know about rotating summer tyres will it help with snow...but do know that all manufacturers recommend that all new tyres are fitted to the rear od the car.... the reason for this being the weight of the engine assists the grip on the front of the car, the extra thread on the back avoids the back end losing grip.... different if its a rear engine car of course...

Ideally you want them on all 4.
On the rear only is safer.
On the driven wheels only gives more traction. Less likely to get stuck.

Seth Brundle

Kategill wrote: »

Don't know about rotating summer tyres will it help with snow...but do know that all manufacturers recommend that all new tyres are fitted to the rear od the car.... the reason for this being the weight of the engine assists the grip on the front of the car, the extra thread on the back avoids the back end losing grip.... different if its a rear engine car of course...

Just to clarify one or two items:
* some car manufacturers do not recommend rotating tyres (e.g. BMW)
* many cars have tyres that cannot be rotated (e.g. mine) due to different widths/profiles, etc.

spank_inferno

Matt Simis wrote: »

However on Haldex it will first try to regain traction lost on Winter enabled front wheels by increasing power to the rears.

Thanks for that Matt.

That makes total sense...... silly question really!

BostonB

Matt Simis wrote: »

....
However on Haldex it will first try to regain traction lost on Winter enabled front wheels by increasing power to the rears. Those rears have summer tyres on, meaning when the power goes to them they will quite rapidly loose traction and spin. Forcing ESP on in a big way to brake those wheels leading to all sorts of weird behaviour....

I would assume it directs more drive forward if it detects slip on the rear, thus winters on the front would be better than two on the rear. But thats a guess, I don't honestly have a clue.

opinion guy

spank_inferno wrote: »

For those with Haldex all wheel drive systems.

If the cost of purchasing winters seems excessive, would it be sensible to purchase 2 winters for just the front wheels?

Seeing as most of the torque goes to the front, this would be ok wouldnt it?
Or would it work against the car if some torque is going to the rear?


many thanks

Why do you say most torque goes to the front ?

Matt Simis

BostonB wrote: »

I would assume it directs more drive forward if it detects slip on the rear, thus winters on the front would be better than two on the rear. But thats a guess, I don't honestly have a clue.

Yes of course, but for the power to be divert to those rears in the first place the front would be slipping (aside from whatever split Audi have it trying to maintain). Catch 22.

opinion guy wrote: »

Why do you say most torque goes to the front ?

He is correct though, Haldex is a FWD biased AWD system, pending generation as much as 95% FWD bias outside of slip and TC issues.
http://en.wikipedia.org/wiki/Haldex_Traction

opinion guy

Matt Simis wrote: »

He is correct though, Haldex is a FWD biased AWD system, pending generation as much as 95% FWD bias outside of slip and TC issues.
http://en.wikipedia.org/wiki/Haldex_Traction

This might be true in the general sense but is not true in all cases

http://www.audi.co.uk/audi-innovation/our-technologies/quattro.html
select link 'quattro for cars with transverse engines'

Audi UK wrote:

To ensure the optimal distribution of engine power for each model, Audi uses specially configured all-wheel drive systems that vary in design.
The Haldex clutch is an electronically-controlled multi-plate clutch. It performs the function of the Torsen centre differential in cars with transverse engines, such as the Audi A3, A3 Sportback and Audi TT.
It ensures that engine power is permanently distributed between the front and rear wheels as and when required.
The Haldex clutch works by reacting to differences in the rotating speed between the front and rear wheels. This causes variations in the system’s hydraulic pressure, which in turn compress the clutch plates together to balance the distribution of power between the front and rear wheels. So if the front wheels begin to lose traction, the Haldex clutch channels power to the rear. And the greater the difference in rotational speed, the higher the pressure applied to the plates – which means that more engine power can be transmitted to the rear wheel.

Default on Audi Haldex is 50/50 front/rear split with ESP on AFAIK. Turn off the ESP and you get front 40/rear 60. Which means you can powerslide and do donuts in an A3 quattro or TT quattro - though it isn't easy to overcome the natural grip of the AWD

example:
http://www.youtube.com/watch?v=V6OM_-sLfIY

Boots2006

Nope, given similar grips levels on all 4 wheels, its up to a max of 50:50, and typically 95 front : 5 rear

Here's the youtube link you should have posted, you can clearly see the fronts slipping first, then the rears being brought in.
http://www.youtube.com/watch?NR=1&v=tTjkh-bgBJs
-that guy probably didn't realise that the handbrake deactivates the haldex

Loads of detail here http://www.vaglinks.com/Docs/Misc/HaldexTraction.com_Haldex_AWD_Traction_System.pdf

Matt Simis

opinion guy wrote: »

This might be true in the general sense but is not true in all cases

http://www.audi.co.uk/audi-innovation/our-technologies/quattro.html

I still disagree. Have a look at the Audi page again. It says permanent split yes. A 95Front 5 Rear split is a permanent split!

It also clearly says in your own quote "So if the front wheels begin to lose traction, the Haldex clutch channels power to the rear. And the greater the difference in rotational speed, the higher the pressure applied to the plates – which means that more engine power can be transmitted to the rear wheel."

There are benefits to a FWD drivetrain, but Haldex is not like the old Torsen quattro (a mechanical split AWD, generally 50:50 with 75% movement possible either way). For majority of [A3, TT etc] drivers the drawbacks of a "real" AWD system (weight, fuel consumption, sheer size) make the electronic FWD focused system more suited.

BostonB

I didn't realise the Haldex was FWD bias. I assumed incorrectly it was RWD bias.

You live and learn.

tossy

BostonB wrote: »

I didn't realise the Haldex was FWD bias. I assumed incorrectly it was RWD bias.

You live and learn.

Yet on my old Halex car rear tyres wore out alot quicker than fronts.

opinion guy

tossy wrote: »

Yet on my old Halex car rear tyres wore out alot quicker than fronts.

Well I'm going by a what an Audi dealer once told me when I say a 50:50 split the ESP on and a 40:60 rear split with ESP off. And I have driven one on occasion and they certainly behave consistently with what I was told. If you turn off the ESP it behaves with a distinct RWD quality and will drift like a RWD car if you push it (helps if ground is wet).

BostonB

Theres different versions of the Halex system, and I assume it can be set up to bias different ways, so it could be different on model to another. Again I assume.

opinion guy

BostonB wrote: »

Theres different versions of the Halex system, and I assume it can be set up to bias different ways, so it could be different on model to another. Again I assume.

Well I did try saying that:

opinion guy wrote: »

This might be true in the general sense but is not true in all cases

.....but everybody shouted at me.........:(


****cries****



Bottom line - if max diff is 50:50 then someonw explain to me how its possible to donut/powerslide a TT or A3 quattro?

tossy

opinion guy wrote: »

Well I'm going by a what an Audi dealer once told me ...

Well considering my local Audi dealer never had haldex service oil in stock until i ordered it and that they didn't have the special tool to remove oil plug i would be weary of anything haldex related they say

BostonB

I think you'd need to be specific about the car model and the system on it.

A Haldex Traction unit may divert up to a maximum 100% of the torque to the rear axle as conditions warrant.

http://en.wikipedia.org/wiki/Quattro_(four_wheel_drive_system)#quattro_generation_VI