Does a tyre retailer bear any responsibility?

[bn1986]

If you goto a tyre retail outlet with a bald set of oem rims/tyres and you tell him you're considering upgrading both rims and tyres..

You explain you only can go 7.5" wide for legalities sake and you specify your preference of tyre size (in my case 205/40/R17 on 17*7.5" rims)..

You then realise after the deals done that hes sold you tyres that are only rated to carry 450kg when infact the oem tires are 83w = 487kg.

As a consumer do i have any leg to stand on. I mean i clearly specified that i needed to keep the rims etc legal and im now stuck with something that doesnt seem quite right...

Peoples thoughts and experiences would be appreciated..

Im not naming nor shaming coz im otherwise pretty happy with the store and ill be consulting them tomorrow.

[rayray086]

There will always be a legality issue when upgrading your stock wheels. Something that one policeman thinks is passable may not hold be the same for the next. If it's any consolation, there are many of us that have upgraded our stock wheels to ridiculous sizes, but we all take that risk in regards to legality issues (and safety in some cases hahaha). If the guys at the tyre shop find a 205/40R17 tyre that falls within your required legal limits, and conform with your requests for an exchange, be prepared to fork out more money on top as no doubt they'll be very expensive tyres. I just had a quick search and pretty much all 205/40R17 tyres are rated at 80W. The next step up to 83W are 215/40 and 205/45 tyres.

Edit: There is a 205/40R17 tyre in 83W, but it's a semi-slick haha (Falken RT-615).

[Diesel_vert]

The maximum axle loads for a 9N3 Polo GTI is 920 kg at the front, and 830 kg at the rear.

Now the rear axle may be fine, but the front axle actually exceeds your current tyre's load capacity of 900 kg per axle.

That's a very dangerous situation to be in (never mind the illegalities) - insist that they replace them with 205/40 R17 84W XL tyres at their cost.

I don't know the exact technical calculations involved in this but as per the "Tyre Bible", one wheel is meant to hold a quarter of the total car weight. I'm gonna assume worst case scenario here and guess that you have the heavier VR6 which comes in at ~1200kg; let's say 1500kg with a full car load. That means the ideal tyre load rating that you should go for is one that can carry ~375kg. Let's also muster in a 10% safety margin (like in the tyre bible), and that will make it exactly ~412.5kg. So if those calculations and my assumptions are correct, that means those 205/40R17 tyres that can carry a load of 450kg which, theoretically would be perfectly safe...

No, you cannot use the GVM (gross vehicle mass) alone for determining whether or not a tyre's load capacity is sufficient. For example, the 9N3 Polo GTI has a GVM of 1700 kg, and four LI 80 tyres have a combined load capacity of 1800 kg. Now this may appear to be acceptable, but as I've shown above, this isn't the case at all. By using this method you end up with a 50 kg excess, when in fact you have a 20 kg deficit.

Or in other words, it's reporting a safety margin when there actually isn't any, so as far as miscalculations go, that's a pretty big one.

The "Tyre Bible" can go shove it.

[bn1986]

hey buddy where did you get those axle load figures from?

[99_FGT]

Yes, you do have a leg to stand on (provided you aren't 5000km's into the tyres, that might test the relationship). They have not provided you with a product that meets the spec's you provided (legal, 17", 205/40/R17). Ask them what they will do.
In QLD and Vic anyway (thanks Diesel_Vert) a tyre with a load rating less than the minimum spec on the tyre placard is not legal.
Al..

[Diesel_vert]

hey buddy where did you get those axle load figures from?

From a 2005 German brochure (PDF, 1.2 MB) and a 2008 UK brochure (PDF, 2.7 MB).

The figures should also be stamped onto a plate affixed to the car somewhere, which shows the GVM (gross vehicle mass), GCM (gross combination mass), and maximum front & rear axle loads, though I'm not 100% sure whether this plate is compulsory or not.

Yes, you do have a leg to stand on (provided you aren't 5000km's into the tyres, that might test the relationship). They have not provided you with a product that meets the spec's you provided (legal, 17", 205/40/R17). Ask them what they will do.
In QLD and Vic anyway (thanks Diesel_Vert) a tyre with a load rating less than the minimum spec on the tyre placard is not legal.
Al..

It's probably the same for NSW, but it's not so much the illegality that concerns me - it's the fact that his current tyres are technically unsuitable and not fit for service.

[bn1986]

in NSW its VSI09 which provides the governing rules for changes to wheels and tyres, page 4 states

"any replacement tyre must have a load rating equal to or better then the rating of the original tyres fitted by the vehicle manufacturer"

[brad]

You then realise after the deals done that hes sold you tyres that are only rated to carry 450kg when infact the oem tires are 83w = 487kg.

As a consumer do i have any leg to stand on. I mean i clearly specified that i needed to keep the rims etc legal and im now stuck with something that doesnt seem quite right....

If the size you chose was under-spec they should point this out to you. ie: transfer the responsibility. If they haven't told you the new tyres are under-spec then they should provide a solution to your current dilemma. Note that the solution might be more expensive tyres. They should take the old tyres back & only charge you the difference.

When I used to sell tyres, I would point out to the customer that their choice was under-spec and the package was "for off-road use only" (we even had a stamp). It was up to them if they wanted to proceed of be guided by our alternative suggestions.

[rayray086]

No, you cannot use the GVM (gross vehicle mass) alone for determining whether or not a tyre's load capacity is sufficient. For example, the 9N3 Polo GTI has a GVM of 1700 kg, and four LI 80 tyres have a combined load capacity of 1800 kg. Now this may appear to be acceptable, but as I've shown above, this isn't the case at all. By using this method you end up with a 50 kg excess, when in fact you have a 20 kg deficit.

Or in other words, it's reporting a safety margin when there actually isn't any, so as far as miscalculations go, that's a pretty big one.

The "Tyre Bible" can go shove it.

I'll withdraw my statements.

[Diesel_vert]

The size shouldn't be an issue, as 205/40 R17 84W XL is actually the homologated fitment for the 9N3 Polo.

The problem is that they've fitted standard load tyres instead of extra load tyres as required.


As for choice, well, there's plenty to suit all budgets...

BFGoodrich g-Force Profiler
Bridgestone Potenza RE001
Continental SportContact 2
Dunlop SP Sport Maxx
Falken FK452
Falken Azenis RT-615
Federal 595 EVO
Hankook Ventus V12 evo
Hankook Ventus S1 evo
Kumho KU31 Ecsta SPT
Kumho KU39 Ecsta LE Sport
Marangoni Zeta Linea
Maxxis i-PRO Victra
Michelin Pilot Sport 3
Nexen N8000
Pirelli P Zero Nero
Toyo Proxes T1R
Toyo Proxes R888
Yokohama S.drive

... all of which are available as 205/40 R17 84W XL.

[Spec83]

I heart my T1R's

[bn1986]

he swapped them for KU31s..

[99_FGT]

OK, not a bad outcome. Or did you feel you had better tyres before?
The KU-31's are soft, and go off early on the track, but for road use I found them to be grippy and predictable. But not long lasting really.
Al..

[Diesel_vert]

Glad it's all been sorted.


BTW, here are the factory inflation pressures for the 9N3 Polo GTI:


205/45 R16 83W

Half load - Front: 2.6 bar (38 psi) / Rear: 2.4 bar (35 psi)

Full load - Front: 2.8 bar (41 psi) / Rear: 3.2 bar (46 psi)


205/40 R17 84W XL

Half load - Front: 2.8 bar (41 psi) / Rear: 2.6 bar (38 psi)

Full load - Front: 3.0 bar (44 psi) / Rear: 3.4 bar (49 psi)

[bn1986]

Originally had Dunlop sp 9000s

Not sure if they were better / worse