OK, this is a little long, so bear with me. I hope it might help someone else, and maybe one of you can explain it.

I have an '05 MC with Holeys and Conti's. I like them, a good highway tire, but I wanted to experiment a little and maybe try an autocross or two. I picked up 4 15" R82 Silverstones on Ebay for 100 bucks and ordered 4 Kumho 195/60 Ecsta HP4 716's from TireRack. Tires arrived, I had them mounted, and I put them on the MC. They feel ok, not as nimble as the Conti's, but they hang on better in the curves, but after about a hundred miles, I notice that if I'm going down a freeway at about 65, drop it in 4th and punch it, the car pulls to the left. Back off, and it goes back to center. WTH ?!? Fearing that I had popped a bushing or something, I take the Kumho's off and put the Conti's back on. Everything is fine again, straight as an arrow.

Well, now I'm puzzled, and I start looking closer at the Kumho's. It seems that tires come with a little red dot on them, the tire guys tell me that you should try to line that up with the valve stem. The installers did just fine, all the dots were at the stems, but as I look closer, I notice something. Tires have 2 sides, the Kumho's had the DOT mark and the serial number on one side. 3 of them have the red dot on the opposite side from the serial number, but 1 of them had the red dot on the SAME side as the DOT stamp and serial number. It's almost like Kumho goofed and put the red dot on the wrong side of one of the tires. So I take that tire back to my installer (Mock Tire, great people) and explain my theory, and he says no problem, we'll flip that one for you. This morning I put the Kumho's back on, take her for a ride, and bingo, problem solved. Straight as an arrow.

Now I don't know if tires have one sidewall built differently from the other or what, maybe the outside one is stronger or something? These are not directional tires, so you wouldn't think it'd make much difference, but it sure does. I guess the lesson is, pay attention to the 2 different sides of your tires, and make sure they're all the same. Maintain symmetry.

Anyone have an explanation, or something to add ? Any tire engineers out there ? Alex ?

 

Years and years ago, I spent time hanging out in a gas station that mounted tires. (Remember when they were called service stations?)

Anyway, they told me that the serial number was always mounted on the inside to prevent it being rubbed off if the driver rubbed the curb.

I don'tknow what's going on with your tires though.

 

I still call them service stations. But people look at me funny when I say that over here.

 

i thought that dot was there to have the higher qualified tire mounting
people to do match mounting. not sure if the valve stem is the 'right'
match location or not on the wheel. usually wheels have a dot on them,
i think (if i can remember correctly).

i wouldn't be surprised if the dot was placed on the wrong side of the tire.
probably just operator error and since those are non-directional tires
(all seasons?) they probably just let it go thinking that you wouldn't notice
a difference.