What constitutes a Heat Cycle?

[GTIIIL]

I haven’t been able to find any info on the definition of a heat cycle on tires. I have 6 1/2 hour sessions on my new PSC2 tires on a full road course (Big Willow). Any estimates on how many heat cycles that is and how many should I expect to get out of them?

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[shogun32]

6 cycles. Assuming you've got ~1hr between sessions. Use heat blankets if you want to reduce the cycles to 1 per day.

 

[Brian@BMVK]

I haven’t been able to find any info on the definition of a heat cycle on tires. I have 6 1/2 hour sessions on my new PSC2 tires on a full road course (Big Willow). Any estimates on how many heat cycles that is and how many should I expect to get out of them?

Technically any time you warm and cool the tire, that's a heat cycle. The reality is they're not all equivalent. A street heat cycle doesn't have the same effect as a track cycle. For HPDE sessions, each session is considered "1 cycle".

 

[GTIIIL]

Thank you for the replies. I know that it is only an guesstimate as to how cycles you can get out of a given tire, so if the # of heat cycles is hard to estimate, what does the tire feel like when it is heat cycled out? It's obvious if the tread is worn through, but the heat cycle isn't so easy to see.

 

[shogun32]

18-30 heatcycles is a reasonable rule of thumb I think. Tires that are blued, or when cool are really, really hard is an example of expired tires. You should also be able to tell as you're driving them that whereas when you previously came into a corner and did certain things the car acted a certain way and now you get different behavior is a clear indicator.

Tread remaining (even in seemingly good condition) is a lousy indicator of cooked or not.

 

[GTIIIL]

Yes, I understand that the heat cycle age doesn't present itself like a worn tread does. Never having heat cycled a set of tires before; this will be my first set, so at least I have some idea what to expect. Thanks.

 

[Brian@BMVK]

Thank you for the replies. I know that it is only an guesstimate as to how cycles you can get out of a given tire, so if the # of heat cycles is hard to estimate, what does the tire feel like when it is heat cycled out? It's obvious if the tread is worn through, but the heat cycle isn't so easy to see.

It's extremely tire dependent. Most tires, outside of a sprint or qualifying-type slick, when used for HPDE/long sessions will wear out or cord before they cycle out. The faster & softer 200tw tires will usually heat cycle out and get hard and slow before they wear out in something like autocross, though.

 

[Chris2020GT500]

Thank you for the replies. I know that it is only an guesstimate as to how cycles you can get out of a given tire, so if the # of heat cycles is hard to estimate, what does the tire feel like when it is heat cycled out? It's obvious if the tread is worn through, but the heat cycle isn't so easy to see.

The tire manufacturer should be able to provide you with this information. Also, a heat cycle is from HOT temp all the way down to COLD. However, as others have said, using the tire warmers brings the tires down from HOT to COLD slowly which reduces the cycles.

Also, you will feel when a tire is out of heat cycle as you will not be able to hold your line, you will feel the tire pushing and it will get worse as the tire drops off.

It's similar to what I did with my race tires when I raced motorcycles and why tire warmers were so important. Not only for having the tires hot at race start but also reducing cycles and preserving the performance.

 

[nbjeeptj]

I had a set of R888R's (100TW DOT race Tire) only go 13 20 min sessions and were hard as a rock and worthless but I have had a set of Federal 595RS-Pro (200tw) set go 34 20 min sessions and I made it to cords and never felt a big traction drop off like the R888R's.

 

[Norm Peterson]

It's extremely tire dependent. Most tires, outside of a sprint or qualifying-type slick, when used for HPDE/long sessions will wear out or cord before they cycle out. The faster & softer 200tw tires will usually heat cycle out and get hard and slow before they wear out in something like autocross, though.

I certainly noticed the heat cycle effect on a set of RT615 Falkens some years ago at autocross. But dead as they were for autocross, they were still better than fresh all-season tires in, let's call it 'enthusiastic' street driving.

I know my Mustang's 285 MPSS tires aren't what they once were, either. But they have many track session heat cycles on them plus a few thousand street miles ("fractional heat cycles"?). I think they started dropping off somewhere around 20 - 25 sessions.


Norm

 

[Ewheels]

I had a set of R888R's (100TW DOT race Tire) only go 13 20 min sessions and were hard as a rock and worthless but I have had a set of Federal 595RS-Pro (200tw) set go 34 20 min sessions and I made it to cords and never felt a big traction drop off like the R888R's.

Apples to oranges, my friend. R comp tires will usually always heat cycle out before you hit cords. Street tires will usually cord before they heat cycle out.

I have a set of Toyo RR's to put on after my Supercar 3's are done. That'll be my first experience with R comps so I'll have some first-hand experience to report back with

 

[Brian@BMVK]

Apples to oranges, my friend. R comp tires will usually always heat cycle out before you hit cords. Street tires will usually cord before they heat cycle out.

I have a set of Toyo RR's to put on after my Supercar 3's are done. That'll be my first experience with R comps so I'll have some first-hand experience to report back with

You'll be disappointed.

 

[Brian@BMVK]

 

[Ewheels]

Not that I'm in any way, shape, or form a pro driver and my consistency could be all over the place but I don't necessarily agree with these. In my experience, the Supercar 3 was IMMENSLY faster than PS4S.

You'll be disappointed.

I hope not, lol! I got them for 60% off so I couldn't say no.
I've heard good things about them. Not the fastest tire, especially for a slick, but decent and good consistency. Plus I can get a set of 4 for under $1k

 

[Brian@BMVK]

In my experience, the Supercar 3 was IMMENSLY faster than PS4S.

1s on a 72s course is a pretty sizeable amount. Also did you run the same size and age of tires PS4S and SC3?

Hopefully they work out for you. At that price, go for it! The 3R is the one to get in that type of tire.

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