Editorial Comment: 
This is a coding used by Hankook for some of its Ventus line of tires.

We have contacted the Hankook office in Canada and they stated that the ZR means that the tire is rated for operation at speeds of over 149 mph.

Personally, I wasn't satisfied with that explanation because, the codes you provided (225/45 zr16 89 w) contain the speed rating "w" at the end, which seems to be redundant and even possibly confusing.

I inquired --again-- to see if Hankook was using their own coding for this line of tires, and discovered that several, if not all, major tire manufacturers use ZR in some of their tire codes for what are generally known as "High Performance" tires.

The question raised, is why do they still leave the W in the coding if they were replacing it? What they've done seems to be a departure from the existing industry standard in which the "R" preceding the rim size is used to designate Radial construction.

To me, this is confusing, to be mixing a code used for speed with another which designates the construction.

Hankook are not alone in this -- as I stated I've since seen this in the tire catalogs of other manufacturers, but I still find it objectionable because there is a mixing of two purposes into the same code.

If you agree with my thinking, I'd encourage you to complain to your dealer and at any opportunity you have to have contact with any manufacturer.


TG