Have been doing a bunch of research on many "Extreme Performance" summer tires over the last few months. A friend mentioned the "redesigned" 615, the 615K. Couldn't find many reviews on this new version. Was wondering if there might be some owners that have tried them out, or could compare them to the older 615.

My car is currently on XS's. Before that, I was running the Star Specs. I just like the idea of trying new tires out. I'm almost sold on the RE11s, and possibly the AD08s. I'm a sucker for the 615s though, cause I think they look great!

Any feedback would be appreciated!

 

I just bought a set. 255 & 275. I needed tires by next week and these were one of the only sets I could get in time. (thanks nitto 4 week backorder) I'm going the track in 2 weeks. I've used the old 615's but that was years ago. I'll post some feedback.

 

I love the AD08s. They are expensive though.

 

latest grassroots motorsports mag had a review on a bunch of these tires. think the xs came out on top. don't remember if the ad08 was part of that test.

 

i'm curious in comparion to Star Spec's..

 

I run AD08's and I really can't think of a better tire for the S2000. I briefly tested the RE-11's as well, but went with the AD08's after previously having good luck with the AD07's. I've also tested the Star Specs, RS-3 and Kumho XS as well.

All I can say is WOW. What great gripping tires that LAST! I've gone to 4 track days and you could barely tell that they've been used! Not to mention a couple of road trips and weekend driving. For it being a soft rubber compound, I'm very impressed with how long it's lasting.

As for the RT-615k, some guy in an Evo 10 was running them on the track and said they're better than the previous versions, but they still get gummy pretty fast. That's all I've heard of them from a track perspective so take it with a grain of salt.

 

How much longer would you say the AD08s lasted than the Star Specs and XSs? I found the XS to wear very fast. I killed a set in a little over a month. I only ran the AD08s for about three weeks before I left on deployment.

 

the aforementioned latest GrassRoots Motorsports mag said the 615k suffers some of the same attributes of the 615. Once you heat them up they become greasy and it's hard to recover their performance after that. Not exactly a glowing review. On the other hand, grip was said to be improved tremendously over the 615.

 

That is not a glowing review at all. I'm hoping the larger tire will reduce the over heating issues. I'll post some feedback after Buttonwillow on the 31st.

 

Ok back from Buttonwillow and here are my thoughts.

First these tires only had 500 miles on them when I hit the track.

255's up front and 275s in the rear.

Outside temp was 95+

Open session when it was cool the tires had plenty of grip, I was taking it easy and still playing with tire pressure. I found that 38psi hot is where they shined.

Second session I was able to push them for 20 minutes. Good grip the entire session with no sign of them getting greasy. I was shocked. I put down my fastest lap of the day on my 9th lap. One thing I notices is that there is very little noise from these tires at the limit.

Third session it was the hotest point of the day. After 3 hard laps they became greasy and most worrysome is that they just give up with little or no warning. No squeel or noise, just a slide. It wasn't all or nothing, just a very progressive slide. I slowed down for a lap and a half and back on them hard and they didn't improve. They definately do not like the high heat.

I feel that these tires are a good improvement over the previous version but not nearly as good as the NT05's. Not to mention that they cost more.

Just my .02