what happens when directional tires are rotating the wrong way? i know it won't have optimune performance, will it blow up at high speed or veer weirdly?

 

While you might have tracking problems, one of the main reason for directional rotation is to facilitate water evacuation.

They won't blow up but they won't perform optimally as they were designed to perform.

 

they will also wear faster

 

And if u were to switch them ( one direction to the other ) when they had some miles on them ( even a couple 100 ) U would get Belt Separation

 

I'm doubtful about that one... Does this statement come from the tire manufacturer?

I ran 2 endurance events back in Italy where Michelin was supplying/mounting/monitoring the tires, and when the tire wore down, they just swaped them and we ran them backward. Tires lasted an average of 4 hours (which is pretty good). Granted they were not directionnal, but a seriously doubt this would be an issue.

I'm pretty sure my directionnal KDW's have had close do 100 miles of reverse in them...

 

This is not a directional thing or a Z thing. Since Radial tires were introduced, it has been a rule that what ever way they are put on, that is they way they have to remain.

Hence, when u rotate ur radials, its L/F to L/R and R/F to R/R where as when u rotate ur old style steel belted tires, its L/F to R/R and R/F to L/R. Course on the Z that cant be done due to different size tires F @ R.

A good tire shop selling used radials will mark the tire so they are mounted to rotate the same direction. I was taught yrs ago, how to run my hand over a radial and tell which direction it was mounted and a GOOD tire man can tell by looking at them. I have in my poorer days bought used radials with excellent tread and inadvertantly mounted them wrong and had them separate and disinigrate in short time.

With the belt design of a radial, the belts find there "home" and if that is disrupted then the tire fails.