I have noticed particularly with Michelin & Pirelli tires on the same width rims & same size tires as mine, the tires are not flush to the rims like mine are. They seem to be wider, sometimes sticking out past the rim as much as 1/2-inch. My friend's 911 has this with Michelins and I have seen some F-Types with Pirellis with the same look. Is this unique to the tire or is it a result of the design of the rim? I ask because my new rims stick out a little past the tires and I do not like the look, even though the tires are the correct size.

Thanks and here are some pics as examples.

 

Some of the new tire designs have extended the side wall to prevent rim from curb rash. The tread width is usually not changed but by putting extra rubber it lets the tire take the scuff. The aspect ratio doesn't change nor does the overall circumference/diameter from tires with conventional side walls. I saw the difference when I had new Goodyears installed on my kids Audi. The old Pirelli's had the sidewall feature where the goodyears were flush with the rim. I also believe the run flats have the same construction .Good idea.

 

Correct - that extra bit of rubber is to protect the rim - it is a feature that all low-profile tires should have!

 

That is true, on the other hand it is just rubber, it would only prevent the slightest of curb rash but most likely not all.