Tyre & wheel size legality

[discomarsh]

I spoke to RMS NSW today about the legality of larger wheels. A staff member of the Technical Enquiries Department directed me to Vehicle Standards Information #6, dated 1-Nov-2007.

http://www.rms.nsw.gov.au/documents/roads/safety-rules/standards/vsi-06-light-vehicle-modifications.pdf

This information sheet concerns light vehicle modifications and is gazetted in legislation, according to James at RMS. Importantly, it allows for a 7% increase in rolling diameter.

So, for the RRS, the largest wheel on the placard is 255/50 r19 with a rolling diameter of 738 mm (29.0 inches). A 7% increase allows tyres up to 790 mm (31.1 inches). This allows for a 255/55r20 tyre which is 789mm in diameter.

Beforehand, I had been reading VSI #9, 2003, which is a guide only. It is less favourable to those liking big wheels, cause it suggests not increasing the rolling diameter by more than 15-mm, so would not allow tyres 275/45 r20.

[p38arover]

I don't know why the forum inserts a scrollable AULRO page instead of the linked PDF file but it's happened to me, too. I don't know an easy way around it except by downloading it and then attaching it as I have just done..

[Redhead]

Interesting Facts.
I have recently put some late model 20 " RRS wheels on my earlier model. They were new (1000Klms) and came with 255/55R20 tyres from the factory.
Its good to know that they are legal as I wasn't sure. I would suggest that if anyone is going to upgrade to 20"or 22" they look at getting a set of these instead. Two of the 22" that came with the car cracked because of the low profile tyres and the newer 20" ones fill the guards nicely.
One extra side benefit is that you will get better fuel consumption.

[p38arover]

One extra side benefit is that you will get better fuel consumption.

Not if the rolling diameter is the same - and it should be.

[Redhead]

Not if the rolling diameter is the same - and it should be.

Well its not the same rolling diameter.
What was part of the thread that I was replying too was that you could legally go up in diameter 7%. Thats from 739mm to 790mm.

I have done this and it works. Sure it means the speedo is wrong but I always use a modern Gps with the right warnings etc. I didn't do it mainly for the fuel savings I did it for aspect ratio /comfort/save rim damage, but i'll take the extra 7% anyday.[thumbsupbig]

[wlin88]

Interesting Facts.
I have recently put some late model 20 " RRS wheels on my earlier model. They were new (1000Klms) and came with 255/55R20 tyres from the factory.
Its good to know that they are legal as I wasn't sure. I would suggest that if anyone is going to upgrade to 20"or 22" they look at getting a set of these instead. Two of the 22" that came with the car cracked because of the low profile tyres and the newer 20" ones fill the guards nicely.
One extra side benefit is that you will get better fuel consumption.

Hey buddy have u got a photo of the wheel on your car ? Cheers .

I am about to purchase some new tyres but not too sure about how they fit and look .

Cheers