Bad set of Tires?

[Arnis]

I have had the same set of OEM A032s on my NSX for at least 10k miles and still have a tremendous amount of tread left. I just completed my second track day of the summer on these tires and have not had the usual slight tire melting issue at the end of the sessions that I recall from past track days (I had not been out on the track with the NSX for about 2 years so my recollection is a little foggy). At both of these latest track events, the tires felt like they were holding a lot of heat and the car was getting pretty loose in the afternoon sessions (others noticed it as well). Both days the outside temperature was not extremely hot (in the 80s in the afternoon and the 70s) in the morning.

Could something be wrong with the tires? As background, my driving abilities have improved over the past two years, I was just not doing the driving in my NSX. Also, I have not had the alignment changed or checked since the tires were mounted and set to factory specification.

 

[nsxtasy]

I have had the same set of OEM A032s on my NSX for at least 10k miles

Are you referring to the OEM tires (A022) or Yokohama's R compound track tires (A032)?

10K miles is an awful lot to get on either one. Perhaps that's how many you have on the fronts, but you've replaced the rears during that time?

How old are the tires? It's possible they are less able to cope with heat as they age.

 

[Arnis]

Sorry about that... Typo... I have the AO22H0s not the R-compound AO32s. I had all four tires replaced at the same time about 3 years ago or so. I usually get about 10k-12k out of a set but that is pushing it a bit which is one of the reasons that I am wondering if something is wrong with the tires. It's almost like they are too hard (opinion based on wear and poor traction on the track - doesn't even feel as tight as it should on the street but I don't push it too much on the street other than highway on and off ramps when no one else is around). Could all this be symptomatic of tires that were sitting in a warehouse for a few years and the compound dried out?

 

[nsxtasy]

It's almost like they are too hard (opinion based on wear and poor traction on the track - doesn't even feel as tight as it should on the street but I don't push it too much on the street other than highway on and off ramps when no one else is around). Could all this be symptomatic of tires that were sitting in a warehouse for a few years and the compound dried out?

It's possible; you can click the link in my previous post to check when they were manufactured. I assume you were checking your tire pressures and setting them to somewhere around 33F/40R, measured cold. Or, it could be that your perceptions have changed and you're ready for (or accustomed to?) R compound track tires...

 

[Arnis]

Thanks for the link! It looks like the my tires were manufactured not too much before I purchased them so I guess the age is not the problem. I wonder if I just got a bad batch. The whole thing is kind of strange.

I have not driven on r-compound tires before. I have been focused on improving my skills before moving up the tire scale. My abilities have improved significantly of late so I do know that how I am working the tires is a little different than my previous reference points. An instructor at this past track day recommended that I move to r-compounds but I am just not yet convinced. I have had some pretty good drivers take my NSX out with me as a passenger and they were pulling much greater cornering forces than I am (not on these tires but previous sets) so I still feel that I have improvements to make. The last things that I want to do is get myself in over my head with grippier tires that break loose with less warning . Maybe I am ready but I want to really convince myself of it first.

I am pretty careful about the tire pressures. Off the track, I constantly check the tire pressure to keep things at 33 front and 40 rear (measured cold). On the track, I start each session with about 28 front and 35 rear (will vary this slightly based upon conditions). The temperature about 10 minutes after the session is usually around 35 front and 43 rear.

I am thinking that maybe I should get some new tires and see if the situation improves. Any other ideas?

 

[nsxtasy]

I am pretty careful about the tire pressures. Off the track, I constantly check the tire pressure to keep things at 33 front and 40 rear (measured cold). On the track, I start each session with about 28 front and 35 rear (will vary this slightly based upon conditions). The temperature about 10 minutes after the session is usually around 35 front and 43 rear.

When I was using the OEM tires on the track, I left them at 33F/40R measured cold, and just went ahead and used them on the track. They seemed to work fine for me.

I am thinking that maybe I should get some new tires and see if the situation improves.

You could try that with OEM tires. Or, you could try a different, non-OEM street tire. You might try the Falken Azenis RT-615, which is sort of in between a street tire and an R compound track tire in most characteristics. Or, if you need a tire that lasts a long time (the Azenis don't) and/or does well in rain (ditto), maybe try the Goodyear F1 GS-D3.

 

[dquarasr2]

It's possible the tires have gotten a little less compliant over time.

One key, though, is that you mentioned "others noticed it as well". I assume this means other drivers noticed it in their cars (not "others noticed it as well[while riding with me in my car]").

Don't discount the track conditions. If others noticed the grip being lower, it simply could have been that the track did not offer as much grip as you remember it.

You also mention that it felt as though your tires were indeed getting hotter than you had remembered. That, too, is possible. Again, absent of a pyrometer, checking pressures can tell you whether they were indeed hotter than you thought (approximately 1 PSI for every 10 degrees F).

Try to check the tires immediately after coming off the track for consistent HOT pressures. After 10 minutes they're no longer hot, but their internal temperature is likely nowhere near what would give you a reliable "cold" reading.

This is what the professionals reference when they say they are "chasing the track" conditions. It's a constant struggle to optimize everything with the changing track temperature, ambient temperature, sun, marbles, rubber on the track, etc.

On your next track day, don't be afraid to play with the pressures as the day wears on. Check hot pressure, go up or down one or two PSI, go back out and see how it feels, and keep experimenting until the car feels best (and don't change more than one thing at a time, like shock or swaybar settings at the same time as PSI adjustment).

 

[Arnis]

dquarasr2 - My mention about others noticing it as well was a reference to others as passengers in my car while I was tracking it.

NSXTASY - thanks for help and advice. I will look into the Falkens and Goodyears as possibilities if I have the same problem with the next set of Yokohamas.

As for the tire pressure advice that you both have given me, I will play around with this some more and see how it goes. All of the thoughts and assitance has been much appreciated!

 

[NSXDreamer2]

dquarasr2 - My mention about others noticing it as well was a reference to others as passengers in my car while I was tracking it.

NSXTASY - thanks for help and advice. I will look into the Falkens and Goodyears as possibilities if I have the same problem with the next set of Yokohamas.

As for the tire pressure advice that you both have given me, I will play around with this some more and see how it goes. All of the thoughts and assitance has been much appreciated!

IMO, Toyo RA1 is not more expensive than the 615 and good year, however, I believed they would actually last longer with track use than the other 2 street tires. While I understand your reasoning of staying with street tires, if you already have 5 or more track days at the same track and you are comfortable and getting familiar with the track. It's time to try R compound. The RA1 comes in full tread as rain tire, you won't be able to use the tire's traction until after couple events. Thus you could "slowly" accustomed to them

 

[AU_NSX]

Could something be wrong with the tires? As background, my driving abilities have improved over the past two years, I was just not doing the driving in my NSX. Also, I have not had the alignment changed or checked since the tires were mounted and set to factory specification.

From what your describing I believe your tyres have "gone off" i.e. they have been "heat cycled" and the rubber has hardened.

This reduces your grip and the tyres don't come up to temperature anymore. Plus because the rubber has hardened they last much longer.

This has happened to me with my motorbike tyres... I don't know the techinical term for it... We just say that the "tyres have gone off"

Just replace them...