I just got new tires and the tread on my old tires was almost perfect on the outer area that's visible when you look at the wheel on the car, but when I put the new tires on and took off the old one's I discovered the inner tread of the tires was almost down to the metal. What causes such an uneven wear to occcur? More importantly what do I do to fix it, alignment? I was thinking it was alignment, let me know what you think because I'm going to the dealer this week for oil change but don't want to schedule an alignment to be done if that isn't the problem. - thanks

 

Get an alignment. If there is a problem, it can be corrected. With the S2K, you can expect inner tire wear (due to negative camber setting) even after it is aligned properly though.

 

You can't have even wear across the tread AND have the kind of handling this car generates. You must pick one or the other. Take a look at any of the newer "performance" cars from the rear and you'll see this same sort of aggressive camber. You'll see it on most BMWs, Miatas, even the Porsche SUV, to name but a small number. If you want long life and even tread wear, then dial out all the camber, toe. You'll have one of the crappiest handling S2000s on the road, but you'll be able to boast about the great tire wear.

 

I understand about the camber after you explained it, it makes perfect sense. I just figured that cars with altered/aftermarket suspension's usually get the issues with camber. xviper do you think i should do alignment anyway? I just had no idea tires would wear that uneven from factory suspension specifications. let me know - thanks

 

If you own the car from new and never had it aligned and your tires wore out on the insides much faster rate than the outsides, then you should get allignment check and align to OEM specs if it is out of specs.

After allignment is checked and corrected if necessary, one thing you can do to extend tire life by about 10-30%, is to flip the tire inside out when the center tread goes down to just before half life, assume that you don't have asymmetric tread design tires.

 

It's very hard to advise you to get an alignment without seeing the extent of the tread wear pattern. Many people have reported OEM tires on OEM alignment settings needing replacement before 10K miles, while others can go as much as over 20K miles. It all depends on the style of driving and exact alignment settings and the tire pressures used.
In general, if you are getting 15K to over 20K on the rear tires, you are pretty average. The fronts usually last almost twice as long as the rears. That's just the nature of this car. If you have even wear (symmetrical from left to right), with adequate life, then leave it alone. Part of the decision to get an alignment depends on your ability to "read" the tire wear pattern. Your tires are telling you a story. It depends if you can understand what they are trying to say.
A few owners have elected to abandon the handling for maximal tire life. This can only be a choice each individual can make.

Oh, and that "flipping" thing, have a look here:
https://www.s2ki.com/forums/showthread.php?s=&threadid=128526

Myself, the car is over 5 years old and I have not had an alignment done yet. I read my tires and I am happy with the story they have to tell.

 

I bought the car used so I'm not sure how long the tires were on for originally, but the tread wear wasn't even close to being even in any way my tires were drastically worn on the inside. the outer tread of the tire looked perfectly fine and had about 80-85% tread left but the inner tread probably aroung three inches from the inside of the wheel was completely down to the metal w/ 0% tread. I understand the camber causes the inside of the wheel to wear faster, but it shouldn't be this drastic a difference, right? Also, the alignment doesn't cause the steering wheel to pull in any direction it goes straight and feels and handles good.

 

If it has a lot of negative camber it will do just what you desribed on the inside of the tires. It does improve performance and give more clearance but the tires will wear quicker on the inside.
If I can help with the tires let me know.

 

As Jim said, your car has too much negative camber to effect the inside wear that much. You're needed alignment.

Even after your car is alligned to within specs, the inside still wear faster than outside dues to small amount of negative cambers. You still need to flip the tires at about half life to extend tire life.

 

did you lower your car? what springs?