RE71RS: "heat cycles" and competitive life

The GRM tire selector guide and tests have been fantastic to determine beginning of life pace, mid life pace, heat tolerance, cold run grip, wet traction, you name it for the most popular rubber donuts.  About the only thing it doesn't address is the competitive heat cycle lifespan or range of 200TW tires.

While GRM found that the RE71RS even gains pace as it wears down, it wasn't evident what sort of heat cycle life they are seeing from the RE71RS particularly.  I've heard anecdotal stories that the Falken RT660 heat cycles out WELL before it's out of tread (not a terrible thing if you want to drive home in the rain while the tire is still in its competitive life), but that the A052 is "fast to the cords". 

Friends have argued: Sure, your RT660s are inexpensive, fast, and last a long time, but the number of competitive runs is actually lower than an A052.  So that even though the A052 tire wears quickly, you get an overall greater number of runs near the pointy end.

All that stated: What have folks here found from the RE71RS?  Is it like the A052 (good till the last run?), heat cycles out and falls off hard like the RT660, or something in between?

[Yes, there are many variable than could impact a tire's competitive life, like driving style, vehicle and tire size, and event type (autocross, track) and style.  Feel free to comment your usage conditions]

For instance: I found that the Kumho V730 in 255/40/17 on a Mazda RX-8 used for both autocross and time trials lasted more than a full season and didn't really seem to fall off hard until near the wear bars, ~2/32" tread remaining.  The pace is not top-tier, but the value is undeniable as you get long tread life AND a pretty long competitive life.  My car will generally heat cycle out tires before the tread is gone, hence this inquiry.

Excellent question, I'm waiting to find out the answer. I'm on my second season with the RE71RS, but they've only seen autocrosses, no track time. So far they seem to be holding up, I've won the last three autocrosses in my class (not to brag, ha ha).

I didn't think the Falken heat cycled out.  I've only had them get hot and greasy and generally wear quickly right from the get go.  However, this was track days and cheap car races, not autox.

I could see that on track, but for autocross it's an accomplishment if you can get them to the wear bars before they're so dead that they're borderline dangerous. Usually in the 150-200 run count range.

In reply to dps214 :

No E36 M3?  They were badly on track compared to other 200tw tires.

Weird that the slight difference would make such a big impact.

On our 1/4 mile paved oval tires lose one to two tenths per lap every race day. It is a very reliable indicator of the effect of heat cycles.

I have  been recording the total miles and run count on the RE71rs tires on my E Street miata.

My video review may begin to answer your question. More current comments are below.

I'm at about 75 runs on the second set, without checking the data, I don't know how many miles. This will be the last set to get any street miles, I own a trailer now. Through 75 runs, they're still very fast. Two events ago, I raw timed a friend in his STR NB2, by enough that he came to talk to me after the event. He was on a brand new set of Falkens.

The first set, which is the one reviewed in the video, was noticeably losing pace as it approached 100 runs.

I also autocross my 8th generation civic coupe on the Bridgestones. Despite being a 1.8, with an open differential, I have been doing very well with it. I lost track of how many runs I had on them, probably around 50, plus the GRM Challenge track day at the Firm, and I replaced them because of the new ones being on sale. I am sure I jumped the gun on replacing them, I had assumed that I would kill them at the track day but they didn't fall off at all.

Be aware, I may be more dependent on having good tires than some. At 68, with only six years of autocross, I'm the oldest driver with the least experience that can still be at the pointy end of our local events.

Thirteen HPDE sessions so far this year on a 3900lb Cadillac ATS-V with two interstate round trips from my house to NCM, 275/35 front (18x10 wheel) 295/35 rear (18x11 wheel).  I hope to get another full day (5-6 sessions) out of them.  

Camber is currently -3.0 front, -2.2 rear, target 34-35psi hot.

Here were 295/30 RE71RS rears on a 18x10.5 last year (2023) after 13 HPDE sessions:

I threw my PS4S streets on the rear and kept sending it, here were the fronts after 16 total sessions:

Camber in 2023 was -3.0 front, -2.0 rear.

There's a GRM story regarding this: https://grassrootsmotorsports.com/articles/how-optimize-tires-quicker-laps-and-longer-life/

But the TL;DR is this ==> it depends.

Not all heat cycles are the same.  Heavy car, smaller tires, high ambient storage = more effect.  Small car, big tires, cool storage = less effect. 

The Triple Threat ND falls into the latter camp.  We have run our fastest laps ever in that car at 1- 2/32nds worn down from new via LOTS of short sessions.  I typically drive to./from the track, do three 6-lap sessions and drive home (45 minutes).  Stored in climate-controlled shop between.

I will say that they get edgier as the cycles go up, but you also get more intra-session consistency...the latter at the expense of a touch more warm-up needed.

Autocross, with it's short but intense cycles, seems to give less optimal cycling.

PS: The last bit of this test shows how quick worn-down, cycled A052's can be: https://grassrootsmotorsports.com/articles/r-comp-tire-test-hoosier-goodyear-yokohama/

Floating Doc (Forum Supporter) said:

I have  been recording the total miles and run count on the RE71rs tires on my E Street miata.

My video review may begin to answer your question. More current comments are below.

https://www.youtube.com/embed/lZIDxKMK7fQ?rel=0

I'm at about 75 runs on the second set, without checking the data, I don't know how many miles. This will be the last set to get any street miles, I own a trailer now. Through 75 runs, they're still very fast. Two events ago, I raw timed a friend in his STR NB2, by enough that he came to talk to me after the event. He was on a brand new set of Falkens.

The first set, which is the one reviewed in the video, was noticeably losing pace as it approached 100 runs.

I also autocross my 8th generation civic coupe on the Bridgestones. Despite being a 1.8, with an open differential, I have been doing very well with it. I lost track of how many runs I had on them, probably around 50, plus the GRM Challenge track day at the Firm, and I replaced them because of the new ones being on sale. I am sure I jumped the gun on replacing them, I had assumed that I would kill them at the track day but they didn't fall off at all.

Be aware, I may be more dependent on having good tires than some. At 68, with only six years of autocross, I'm the oldest driver with the least experience that can still be at the pointy end of our local events.

Finally got around to watching the video, i bet the (old) rivals will feel pretty awful in comparison!  if i wasn't lazy and stored my tires between events i guess they'd last longer.  i have one car that i use for daily and autocross and timetrials and don't bother changing tires or pads throughout the course of an entire racing season...

In reply to flyin_viata :

impressive for a heavy powerful car!  did the car get a lot looser going to PS4s on the rear?

Matt Huffman said:

In reply to flyin_viata :

impressive for a heavy powerful car!  did the car get a lot looser going to PS4s on the rear?

Definitely down on rear grip with worn 71RS front and 80% PS4S rear, but was fine for HPDE...never really experienced oversteer but had to be a bit more judicious rolling power off a corner.

These are from the front of my Elantra N after six autocross events, so about 30 runs, and four 20-minute track sessions, the last 3 in temps over 90 degrees.  (I run different rear tires, so no rotation front to back to even things out.)  I still had plenty of grip and plan to run autocross them until they are truly spent.