I now have 6 track days on my Nitto NT01s and they are nicely worn down to just the two longitudinal grooves with lots of tread left.

How do I tell if they may have been heat cycled to their limit even though they are not yet work out?

This is my first time using R-comps

 

I'm not expert on R-comps, but I believe the general idea is that if you start to feel like they're no longer giving you the level of grip you expect (given the last few events you were on them), then their done.

I've heard that many R-comps are at their best for the first few heat cycles, then stabilize to a pretty consistent level of grip for the duration of their life. Once they start to feel "oddly slick" when the road itself isn't slick (i.e. everyone else isn't commenting on the track changing), you might suspect their done.

If you're consistent enough you could also tell by lap times falling off despite you doing everything you can to stay the course. I'm not sure I'm that consistent, so this isn't yet an option for me. However, I have heard others reflect on just how soon they become slicker. If you're consistently able to run a full 15 min. before the grip starts to drop off, but then it's only 12 min. before that's happening, they may be on their final legs.

I can say with some degree of experience that a hot street tire (like Toyo R1R or Dunlop Direzzas), when they start to feel like they want to give you the slip angles of an R-comp just to stay on the road, they're heat cycled out. Don't ask how I know...there will be a write up once certain legalities are out of the way.

Best,
-j

 

I haven't found the 01's to heat cycle. I've run several sets until they showed cords. They may loose some grip but they don't go off like some of the Hoosiers do.

 

You still of tons of life left in them. The NT01 (and RA1/555RII--same tire compound for all three) don't seem to fall off with heat cycles. Basically, you will wear them out before they heat cycle out. Heck, most people get the fastest lap times right as they are cording.

 

Well on the weekend I answered my own question by setting a new personal fastest lap at a local track during the 7th day on the tires.

Video and details to follow.

 

Guess you were inspired by the Vipers, eh Colin.

Sure looked like you were flying around that last section.

Good show.
Cheers.