Questions about changing wheels.

[Diesel_vert]

Thanks for all the info, It might be just easier to stick to OEM Vw 17 or 18 inch wheels..

One more question, would it cause many problems if i were to get 18s and stick 225/45/18s on them rather than 225/40/18s to give it a bit more comfort and fill the wheel arches a bit better with my stock suspension?
My speedo is already out, currently at 93km when speedo is showing 100km. so 7km out.

thanks

You can go from 225/45 R17 to 235/45 R17, or 225/40 R18 to 235/40 R18.

[The_Hawk]

Just to complicated things, your speedo is actually not out at all... It just under reports your speed!

Your odometer is bang on and if you have a MFD your average speed is also correct.

To see for yourself, next time you are on the freeway set your cruise control to 110km/h and bring up the average speed display then reset the counter. What will the be displayed is the "average" of your current speed... Not its not 110...

[Dutch77]

Just to complicated things, your speedo is actually not out at all... It just under reports your speed!

Your odometer is bang on and if you have a MFD your average speed is also correct.

This is correct. The guys who run Autopolar FIS+ can access the 'real' speed on their MFDs.

[Guest001]

This is correct. The guys who run Autopolar FIS+ can access the 'real' speed on their MFDs.

As can we who have the secret menu in an RNS510 Thats how I know how far out mine is.

Your speedo actually over overstates your speed and must do so by law.

The ADR rules say a speedo shall not show a speed less than actual and may over estimate it by up to 10% plus or minus 4%.

My Cruiser was bang on all the way The VW are atrocious but legal.

[dylan8]

Thanks for that, I didn't think of that until after I had posted I was so caught up in getting the right reference and reading it


Reading through the VIC rules and it seems to come up much the same, no more that +/- 15mm the largest/smallest diamater wheels, no fouling and no more than 1" wider than the widest stock wheel.

Again, everything is written around bigger or smaller than the biggest or smallest rim. If you pick something they same size as a stock wheel you should be right.



Interestingly VIC also lists this where NSW doesn't seem to:

I havnt read the regs for a year or two.
but I thought it was 2" bigger then the largest size on your placard 1" wider then the widest on placard.
is the +/-15mm in relation to tyres or wheel diameter? tyre diameter will make more sense, ill have a look

[Guest001]

[QUOTE=dylan8;939743]I havnt read the regs for a year or two.
but I thought it was 2" bigger then the largest size on your placard 1" wider then the widest on placard.
is the +/-15mm in relation to tyres or wheel diameter? tyre diameter will make more sense, ill have a look[/QUOTE

Is overall diameter Use the tyre comparator in the first reply and you can see what you can use legally

[The_Hawk]

I thought it was 2" bigger then the largest size on your placard 1" wider then the widest on placard.

I was the same, it looks like it has been changed to this instead as it talks to total wheel size (including tyre) rather than *just* the rim. Mind you if I read it correctly it opens the door to stupid big wheels with rubber painted on...

[Diesel_vert]

I was the same, it looks like it has been changed to this instead as it talks to total wheel size (including tyre) rather than *just* the rim. Mind you if I read it correctly it opens the door to stupid big wheels with rubber painted on...

Requirements regarding the load index limits the range of tyres that can be fitted on the vehicle.

[Guest001]

I was the same, it looks like it has been changed to this instead as it talks to total wheel size (including tyre) rather than *just* the rim. Mind you if I read it correctly it opens the door to stupid big wheels with rubber painted on...

Exactly and with the roads the way they are who wants 22's with rubber bands on them ROFL IT has always been total diameter as far as I know and QLD did have diagrams to illustrate that

[Diesel_vert]

The regulations in QLD, NSW, VIC and SA all refer to the overall diameter.

As I said, load index requirements limit what can be fitted to a vehicle.

On a vehicle with 225/40 R18 92Y XL tyres (diameter 637 mm), a 225/30 R20 85Y XL tyre (644 mm) would be within limits (< 15 mm), but the load index (85 < 92) would clearly prevent the vehicle from being roadworthy.