Sorry for the Newb question...I am not too sure, but is it time to replace these tires?



The front still looks ok...

 

In my opinion, for the street driving in the rain, I'd say the rears need replacing. Else, have fun with them for a bit more miles..........

 

would one replace when the wear bars are reached? Or when the wear bars are erased?

Still felt like it had a lot of grip in my last twisty road driving...but that's probably the outside of the tire working and not the inside...

 

Technically when you hit wear bar it tells you that you are at a certain thread depth so the tire should be replaced. However, going past those makes the tire effectively more like a slick. Again, not a good idea to drive in rain, but the dry weather grip may even be better depending on tire construction and compound and on these tires the grip should actually increase.

On my GT3, I was running a bit more camber and would check them often and would only change when I would see steel threads starting to show at the inside of the tires.

 

Just got a set of MPSS to replace my cups. The way to go if you're doing more street than track.

 

This is what mine looked like when replaced...



Currently having Bridgestone RE-11s

 

Wear bears are the indicator of legal limit in most places ( Usually 2mm) if they are close you are through the useable street life of the tire.