then how do you explain me keeping all tires at 38 psi and having the front outside tread wear faster than anywhere else?
My first hunch is Cornering, probably. But I thought about it a bit, and came up with some ideas...
I haven't seen the alignment range that Mazda designs this car with, but I can assume that its camber is fairly tame, and the toe-in is nominal as well. But if the car leans into its tires under cornering, and I'd assume it does after seeing videos of it maneuvering, that means the outside tread blocks are going to take a beating on this heavy front end biased car. Like I said, I'd love to see this car (and the MS3) corner-weighted. That would answer a lot of questions! Some brands of tires also have softer sidewalls, which would cause the tire to roll over itself and shear and wear the outside tread blocks first. Some tires have a tread block pattern that is prone to shearing compared with others, though I feel this tire is not one of these. Finally, it is possible that your alignment has too much toe-in.
So to review, the possible things I see happening with premature outside edge wear:
1. Very aggressive driving style that is forcing the front end to plow. (I don't know the answer to this, only you do.)
2. Excessive toe-in aligment settings
3. Too tame of a camber setting, combined with a soft stock front swaybar which is causing the tire to be leaned on in corners
4. The car weighs a lot on the front corners
5. The tires are prone to wear this way, due to soft sidewalls (not likely, IMO)
BTW, I imagine for Drover's rear tires the fact they are wearing so aggressively in the center has something to do with the fact they were inflated to 38psi in very, very cold temperatures (he mentioned 1 degree...I'm unsure if it is Celsius or Fahrenheit he was referring to but either way that is COLD), and typically you need to compensate for temperature with roughly 1 psi per 10 degrees F ambient change.
I had a 2000 Celica GTS with 205/50-16 Yokohama Advan tires, and I remember that those tires wore horribly (despite them having exactly the same wear rating of 140 A A)...I think I got 5000 miles on them, rotating them every 2,000 miles in my garage, before they were racing slicks. So, at least these tires aren't as bad! LOL...those Yokos SUCKED.
Before anybody mentions it...yes I know that Yoko's 140 tread wear does NOT provide a reference point for Bridgestone's 140 rating...they are only used as guidelines within the brand line.
