What's the J rating on wheels?

[Andy Stanton]

I've been looking at the wheel options for my new E Class and the standard wheels are 7.5J 16" 225/55 5 spoke jobbies. A possible upgrade is to the 8J 16" 225/55 5 spoke twin ones.

I understood the 16" to be the profile, i.e the higher the number the bigger the alloy wheel and the 225/55 to be the width of the tyre and size of the tyre wall profile.

So what's the 7.5/8J element?

 

[sym]

I've been looking at the wheel options for my new E Class and the standard wheels are 7.5J 16" 225/55 5 spoke jobbies. A possible upgrade is to the 8J 16" 225/55 5 spoke twin ones.

I understood the 16" to be the profile, i.e the higher the number the bigger the alloy wheel and the 225/55 to be the width of the tyre and size of the tyre wall profile.

So what's the 7.5/8J element?

Width of the actual Rim . . i.e. 7.5 Inches / 8 Inches.

S.

 

[Andy Stanton]

Hmmm. By Rim, do you mean the actual wheel or a particular piece of it? I'm having difficulty getting my head round that (it is early!).

If it's the wheel, wouldn't that mean the tyres would need to enlarge too? I think that's why I'm struggling with the concept.

Thanks Sym.

 

[sym]

Hmmm. By Rim, do you mean the actual wheel or a particular piece of it? I'm having difficulty getting my head round that (it is early!).

If it's the wheel, wouldn't that mean the tyres would need to enlarge too? I think that's why I'm struggling with the concept.

Thanks Sym.

The width of the Rim, without tyre mounted, from edge to edge. Still possible to fit wider tyres than this measurement. Here's a diagram that shows the measurements clearly.

This page gives full details.

S.

 

[Andy Stanton]

Thanks Sym, Very resourceful!

I now understand it.

Andy.

 

[ChrissyBoy]

That page has some really shocking pictures of alloys people have fitted to cars. I mean, who thinks that this Jag looks good:

http://www.tyresave.freeserve.co.uk/carpix/jagdytec.jpg

 

[Shude]

That page has some really shocking pictures of alloys people have fitted to cars. I mean, who thinks that this Jag looks good:

http://www.tyresave.freeserve.co.uk/carpix/jagdytec.jpg

Nearly as bad as this one: http://www.tyresave.freeserve.co.uk/carpix/amgcar17.jpg