I posted this on the C&R forum because this is a track-exclusive application. I want a lot of views from people that track their cars hard - no daily driver comments. The moderators are welcome to move it to Wheel and Tire forum if they see fit.

I am interested to know two things: 1) Do the r888s heat cycle out, and, if so, after how many cycles? 2) If heat cycles are not a concern with this compound, when do they physically wear out?

General info: Age of tires 1 year, size-255/35r18 square; weight of car+driver~2850lbs (+wing and splitter at speed); wear-56 sessions (25-35 min each), and starting to wear through the grooves on the outer 1/3, but the center and inside are have 2-3mm groove left (into the wear bars).

Heat Cycle: Do they cycle out, and when? If I am outside that range, there is no need to flip the tires on the wheel.

Mechanical wear: I have read on other car forums that the r888 and NT01 differ greatly here. Supposedly... The NT01 is made of the same compound down to the cords, so it basically becomes a slick when the grooves are gone. The wear bars are basically there for wet use. On the other hand, again supposedly, the r888 has a harder rubber layer between the cords and softer outer layer. Once the wear bars are gone, they are in the harder rubber and adhesion drops dramatically. While this is an interesting theory, I don't know the contributor. I prefer to get verification from those I trust and have actual experience. Again, if I have used all the soft rubber, there is no need to flip them on the wheel.

 

My experience with R888 was that they heat cycled out long before wearing. They became fun to overdrive the car and beat up but they lost grip after 12-15 DE sessions. I used NT-01 on a different car (civic) to enduro race and thought they held up better for staying "grippy" but in fairness it was 2 different cars and I have only owned 1 set of each.

 

Were they getting loose on you last weekend Will?

 

Yes, but it's been a year since they were new. It's hard to remember how the felt a year ago, and I've progressed a lot over that time, so that makes it hard to compare. In fact, my lap times have improved substantially despite the tires losing grip. I've been working on finding and maintaining the edge of adhesion, so they have served that purpose nicely. I'm ready to move up to slicks and see how well I can drive them.

I picked up a set of take-offs at a PCA club race last year. They are all the same tire, but came off 2-3 cars. Two are marked with 8 heat cycles the others are not marked. I'm curious to see how consistent the grip is.

 

Mine dropped off a cliff rapidly on track day #5, and on track day #6, they were worse than rock hard no-name used tires. Days 1 through 4 though were hilarious though, very sticky!

 

So, the consensus is, r888s are the Fruit Stripe of tires. Very flavorful at first but degrade after a few chomps and quickly taste nasty. After 56 sessions, I've chewed the flavor out of this gum long ago and now most of the color is gone too.

That's good to know. I was working on driving at the edge of adhesion the last few events. I felt like my skill was improving, but I had a hard time getting past 1G in the corners. I was worried my butt dyno maxed at 1G. Based on this info, it seems to be the tires.

 

I can tell you that SpecE30 only ran on the new R888s for like one season before going back to the RA1s because they were wearing strangely and were heat cycling out way before wearing out whereas the old RA1 would be fastest right before it corded. I would avoid the R888 and save them for the internet "track ready" byld guys and big horsepower guys that seem to love to run them on the street.

 

Thanks. Back when I got them, I wanted an intermediate step between ZII and slicks. I originally wanted NT01s because I heard, similarly to RA1s, they are best just before they cord. Basically, they become racing slicks. Unfortunately, NT01s were not available in the size I needed. I was told the r888 was the same, so oops. Lesson learned.

Although, I am pleased I was able to sustain between 0.9-1.1G while sliding out parallel to the track. In that regard, I believe they provided a good learning tool.

 

There's always the Trofeo R's Im really tempted to try them especially since they're a sub-$200 tire. There are some reports that the RE-71s are pulling G #s close to a full slick though...but Im waiting for more data. At $180ish a tire though, hard to beat the performance for the dollar.

Good little chart to go by: https://nasa-assets.s3.amazonaws.com...1--12-9-15.pdf

The Trofeo's are the same # of points as the Proxes RRs! Wow!