Thread: Rim Size

I did some measurements this weekend on one of my Series 2A 15" Sunraysia rims and the 16" Land Rover wheel mounted on the bonnet as a spare. Plenty of photo's to explain how I did this and wrapping up with a question as to how to determine the actual offset. There's also a bit of a question about the contradiction I have on the rim numbering when looking at Diana's post.

I started with the Sunraysia rim. I used the tape measure only to get a straight edge between the bead protector edges across the wheel. The rule then measures the distance between the wheel at the stud holes and the tape.


So the front, or outside, of the Sunraysia rim measured at 98mm.


Same done on the back, or inside of the rim ...


... produced a measurement of 122mm.


Now, my understanding of "rim offset" is that it is a measurement of the distance away from the centre of the rim from the mounting flange of the rim. So the width of the rim in this case is 98+122=220mm and therefore the centre is 220/2=110mm. The offset is therefore 110-98=12mm.

Now, onto the Landy rim.
Same process for the measurements reveal 27mm for the outside ...


... and 129mm for the inside.


Same calculations then to determine the offset at 51mm. I'm picking that my measurements of the Landy rim might be out a bit due to the thickness of the rim flange and the "upturned edge" at the perimeter of the stud holes. if I don't assume this then I end up with a rim just over 6" wide whereas I'm pretty sure it should be either a 5.5" or 6.5" rim on a Landy. So if I allow a few extra mm for the flange thickness and the upturned edge I can stretch my imagination to say it's a 6.5" rim.

This is where things get a little interesting though. I made that assumption to suit Diana's information earlier in this thread. The problem is that the number stamped on the rim is quite different to the numbers in Diana's list for anything but a 5" SWB.


Maybe this is because the rim is Australian made:


So now I'm not really sure about what offset I'm supposed to have if I'm to revert back to standard Land Rover sized rims. Anyone care to comment on my process and findings?

Any Perth-ites with a Series 2 or 3 Landy want to do some playing and measuring of their wheels? If nothing else, I'd love to know how a 109" drives with standard sized wheels.

Cheers
John B