New LVVTA tyre-rim size chart.

[Nominal]

12 minutes ago, Kerry-TGI said:

What makes a 195/65 no good for 8" wheel but 195/40 is ok? Just that extra height makes it dodgier?

No manufacturer specs it I guess.

[Bling]

Different sidewall strength / stiffness would be part of it i'd say. Best to call up tyre manufacturers and ask if you need to know proper though.

[Bling]

Probably not. You'll probably find they all go by the LVVTA spec as nothing for them to gain by saying yeah stretch our tyres and we'll take responsibility if you stack it. Too many numpities took stretch too far so now it's tightened up. Any old documents that did exist are probably no longer valid. Why even worry? You don't seem too worried about suspension working properly so just run the tyres you want and deal with any issues that may or may not occur lol.

 

This should still be current: https://www.lvvta.org.nz/documents/infosheets/LVVTA_Info_01-2009_Tyre_Size_to_Rim_Width_Compatibility_Guide.pdf

The above table is also referenced in the WOF VIRM, so can be a fail if the inspector is looking.

[cletus]

that falken thing was fairly short lived

it was only valid for a specific model of tyre which has been discontinued

apparently it was one countries office of falken that released that alternative size chart, and once the main office of falken found out, they said nope, cant be used any more.

 

lvvta continued to accept the falken sheet for that model of tyre. i havent seen any for a long time though

[spiderwebfx]

Falken ZE912 (and some FK452) used to have wider than normal tolerance for rim widths.  The tyre is now discontinued as mentioned above although there are still some sizes available until sold out.

Falken also released a bulletin that basically overrode the technical spec sheet that was released saying that it is no longer valid and to abide by their latest technical data book which lined them up with everything else.

The only advantage with Falken now is that they do still produce some oddball size tyres to suit slightly wider rims that you wouldn't be able to get otherwise. 195/45R14 is a good example of this.

[spiderwebfx]

On 20/05/2023 at 15:23, Kerry-TGI said:

What makes a 195/65 no good for 8" wheel but 195/40 is ok? Just that extra height makes it dodgier?

Sidewall construction and layout is slightly different on lower profile tyres so they load the sidewalls different.

 

[Vintage Grumble]

Has anyone ever failed a WOF for their tyres not being wide enough for their rims? Just wondering if its common, or do most places not GAF?

[AllTorque]

As a WOF guy I have seen stretched tyres that I thought would fail, but were ok according to the LVVTA tyre chart, so if they are outside of the tyre chart specs they must be obviously super stretched and you should fail.

Bloody kids these days. Get off my lawn.

[xsspeed]

I'll grab a Pic tonight, I put some that should be illegal on my 16x9s for test fit purposes only and I'd be keen to get your opinion @AllTorque based on that comment lol, they don't look suuuuuper stretched to me at all

[Vintage Grumble]

https://www.lvvta.org.nz/documents/infosheets/LVVTA_Info_01-2009_Tyre_Size_to_Rim_Width_Compatibility_Guide.pdf

So this is still the go to chart? 

 

[Vintage Grumble]

I was quite surprised to see that lower side wall tyres can be stretched more, seems kinda backwards to my simpleton brain.

[AllTorque]

18 minutes ago, Vintage Grumble said:

So this is still the go to chart?

Yes

[xsspeed]

1 hour ago, Vintage Grumble said:

I was quite surprised to see that lower side wall tyres can be stretched more, seems kinda backwards to my simpleton brain.

makes sense if you think the sidewall construction of a lower profile is probably tougher than a balloon

[Snoozin]

2 hours ago, AllTorque said:

As a WOF guy I have seen stretched tyres that I thought would fail, but were ok according to the LVVTA tyre chart, so if they are outside of the tyre chart specs they must be obviously super stretched and you should fail.

Bloody kids these days. Get off my lawn.

1981 Toyota Starlet KP61 4AGE (341)-Edit by Richard Opie, on Flickr

I present to thee, a fine example of a super scary, gonna crash and kill a busload of nuns, 'stretched' tyre fitment.

[xsspeed]

ILLEGAL

[AllTorque]

 

Thins angle shows the ‘stretch’ better. I suspect most wof inspectors wouldn’t think there was a problem there.

[xsspeed]

[xsspeed]

[AllTorque]

That doesn’t look dangerous to me. 

[xsspeed]

That's a 225/50 on 16x9, where max is supposed to be 8