PDA

View Full Version : Is there a point when tires reach too many heat cycles?



gran racing
08-24-2007, 01:19 PM
I've been contimplating attending a double race weekend but funds are tight and there are only a few others that will be racing in my class. For this event, I'm o.k. with being off the pace a bit compared to how things would be with fresher tires. My original plan was to purchase two new tires and use two others that only have a couple of heat cycles on the rear, but it would be great if I could save that money for another event.

I have a set that has several heat cycles (10 or 11) but still has tread on it. What should I expect when using tires with many cycles on them? Will they be much harder to control the car with, possibly too much so or will they just a bit slower? I know Ray gets full use out of his tires and posted times that were very close to what he was doing with brand new tires.

This may sound like like a silly question but with my old Prelude, I always ran out of tread well before ever having to worry about too many heat cycles on a tire.

JamesB
08-24-2007, 01:29 PM
Dave I ran on one set of hoosiers for the entire season with lots of tire rotation and a few qualifiers in the rain on my RA1's. So I figure they had about 30 heat cycles on them and my lap times where about the same as mid season. Not as good as fresh, but not super greasy either.

I finally killed them early in the season instructing at a 2 day DE when I corded 2 of the tires. Thats when I put on the fresh ones. And I would continue on them if I didnt badly flat spot two of them trying to avoid wrecking someone in turn 1 last race.

joeg
08-24-2007, 02:49 PM
In my experience, Hoosiers never get greasy. They just get slower as they age.

A suggestion would be to clean those old tires and apply some softener treatment. Take a heat gun and a scrapper to clean off all the old pick-up and treat away.

You are probably OK regardless. As long as the tires are not corded or flat spotted, you will do just fine. Notwithstanding the so-called tire engineer experts, as long as there is safe rubber, the tire will perform. They are correct that a tire is fastest out of the box and degenerate thereafter as to absolute performance. (they also will tell you not to chemically treat a tire, but I get many more weekends out of them with it).

Rotate those tires--all the time.

Cheers.

benspeed
08-26-2007, 10:27 PM
Dave,

If you're thinking about the Glen, tires are not nearly as critical as LRP or NHIS. The Glen is pretty easy on the sneakers.

JLawton
08-27-2007, 07:40 AM
Dave,
This weekend I had a new set of tires on the front and tires with 8 cycles on the back (but two of those cycles were the 45 minute races at Mid O in the heat). Had some serious over steer problems in qualifying. Ran the worst times since running in ITB. Moved the now one cycle tires to the back and put new ones on the front and it transformed the car. Knocked 2 seconds off my qualifying time in the second race.........

How fast do you want to go and how much money do you want to spend.............. :blink:

Rabbit07
08-27-2007, 08:02 AM
Dave,
This weekend I had a new set of tires on the front and tires with 8 cycles on the back (but two of those cycles were the 45 minute races at Mid O in the heat). Had some serious over steer problems in qualifying. Ran the worst times since running in ITB. Moved the now one cycle tires to the back and put new ones on the front and it transformed the car. Knocked 2 seconds off my qualifying time in the second race.........

How fast do you want to go and how much money do you want to spend.............. :blink:
[/b]

I have had similar experience with using older tires on the back and newer ones on the front, way to loose when you don't expect it. I would recommend using tires of the same age all the way around on the car. It will be off a bit, but not un drivable.

Greg Amy
08-27-2007, 08:38 AM
I won the '06 ARRC with sticker R6 Hoosiers on the front and and 8-cycle, 1-yr-old S05s on the back. Two weekends ago at the IT Fest we were running 1-yr-old C50 'Kooks on the back and brandy new C51s on the front.

Moral? "it depends". But with Hoosiers, we usually see times increasing - and temperatures decreasing - after 10-12 cycles. As Joeg said, nothing dramatic happens, you just get slower.

(Don't pay attention to Jeff...he's skeared of that car...the back end wiggles and his bowels automatically start to loosen up, too...)

Rabbit07
08-27-2007, 08:43 AM
(Don't pay attention to Jeff...he's skeared of that car...the back end wiggles and his bowels automatically start to loosen up, too...)
[/b]

This may be true, but I like a loose car. When I had SO3's on the back and SO5's on the front I spun the car 4 times in 2 laps. After that I just parked it.... :mad1:

924Guy
08-27-2007, 10:34 AM
Perhaps a bit off the topic, but we've been VERY unhappy with the durability we've been seeing out of this season's R6's... we've been lucky to go 3 weekends before cording... I'm having a little more luck than Doug in the 320i, but my car's always been a little easier on tires... and I think I've been a little better at heat-cycling them than he has. I'm really hoping that Hoosier gets this under control for next year - seems like at this rate, we might as well be running the autocross compound!!! :026: :mad1:

Greg Amy
08-27-2007, 10:45 AM
Vaughn, we just ran 3 hours straight on sticker R6s at Nelson last weekend on Knestis' ITB Golf, and they looked real nice when removed. Hell, I suspect we could *possibly* have gone another stint with 'em...

spnkzss
08-27-2007, 10:59 AM
Perhaps a bit off the topic, but we've been VERY unhappy with the durability we've been seeing out of this season's R6's... we've been lucky to go 3 weekends before cording... I'm having a little more luck than Doug in the 320i, but my car's always been a little easier on tires... and I think I've been a little better at heat-cycling them than he has. I'm really hoping that Hoosier gets this under control for next year - seems like at this rate, we might as well be running the autocross compound!!! :026: :mad1:
[/b]

I have had 2 practice days, 5 qual sessions, 5 races on one set of R6s. I had to buy 2 new front tires ONLY because of contact during a race that shredded them. I still ahve the old ones on the rear and new on the front. Plan to keep it that way through the double this weekend and the last race of the year.

No problems with cording or any signs of abnormal wear. You may need to look at your alignment and pressure setup.

By the way, all that track time includes NOT heat cycling properly. I run them in the morning qual, and then afternoon qual without changing them. Didn't have another set to run at the time to pull them off and let them sit for 24 hours.

924Guy
08-27-2007, 12:19 PM
Hmm, maybe we've got our hands on a bad batch, then? Forgot to add that we've seen about the same out of an ITA 240SX, as well - Doug's brother Bob...

What're you guys working with for hot pressures, these days, and what do your cars weigh? My car's about 2640, and we've been aiming for about 28, but I think we might've drifted a bit to the high side?

Camber - well, I'm running less than most of you guys, between 2.75 and 3 degrees, getting wear very even, only slightly biased to the inside - my car's very stiff. Setups for Doug and me both haven't changed much since last year, were we were getting better durability... No drastic changes, really.

RacerBowie
08-27-2007, 12:35 PM
28 psi hot? Are you still talking about Hoosiers? That is WAY lower than what I have been told to aim for. I have been told by the tire guys down here to aim for 40-43 hot with the R6s, and they are working GREAT for me and lasting 15+ cycles still being grippy.

gran racing
08-27-2007, 12:35 PM
28 hot? That seems awefully low.

Greg Amy
08-27-2007, 12:45 PM
28 hot? That seems awefully low.[/b]
No kidding! Dude, that's our COLD pressure. You want 40 hot.

It's no wonder you're killing those things...

Rabbit07
08-27-2007, 12:50 PM
Mine cold are 32-34 front and 39-41 rear.

28 does seem low.

dickita15
08-27-2007, 12:58 PM
we used to run 40-43 hot but have been told recently the R6 like it a little lower maybe a pound or two.

JamesB
08-27-2007, 01:08 PM
direct from hoosier


Tire Pressure Recommendations For Competition

Traditionally, Hoosier tires have often required higher pressures than other brands. This has changed with the A6/R6.

Roadrace/track applications

Vehicle size
Recommended Hot Pressure
Cold Pressure

1800-2200 lbs.
hot 34-37+
cold 26-31

2200-2600 lbs.
hot 35-38+
cold 27-32

2600-3000 lbs.
hot 37-41+
cold 27-32

over 3000 lbs.
hot 38-43+
cold 27-33

[/b]

924Guy
08-27-2007, 01:13 PM
LOL - glad to see everyone's paying attention - even if I'm not! I was waiting for Raymond to chime in with "Aha! So THAT'S why those dayum 924's are so fast!"

My bad, I did mean to say 38psi hot... as Greg figured, I was thinking of cold pressure as I was typing (which are like 29-30psi)

We used to do more like 40 psi hot, with the S05's, but were told the R6's should be notably lower... I guess maybe not so much, we're just grinding them down with little improvement in lap times, it seems...

OK, thanks for the sanity check... back on-topic! :wacko:

DavidM
08-27-2007, 01:52 PM
I got a new set of R6s at the beginning of the season. I'm up to 12+ heat cycles and they look fine. I'm going to run them for the double SARRC at Nashville this weekend. I've been shooting for 37-38 hot temps.

David

cmaclean
08-27-2007, 04:33 PM
I've always driven on old tires. I pick up tires that guys throw away and run on those. They generally have 6-10 cycles on them when I get them. With Hoosiers the tires are the same, just slower than new. The Toyo RA1's are a horror. They are fine for about 6-8 laps and then they will let go with zero warning. Once they get to that stage you have to basically slow down and suck it up for the rest of the race. They don't come back after that point. When I say slow down I mean 1-2 seconds off the original pace.

As an aside, I bought my first new set of Hoosiers this year (discontinued RS05's) and I am shocked at how good they are.

spnkzss
08-28-2007, 08:41 AM
I've always driven on old tires. I pick up tires that guys throw away and run on those. They generally have 6-10 cycles on them when I get them. With Hoosiers the tires are the same, just slower than new. The Toyo RA1's are a horror. They are fine for about 6-8 laps and then they will let go with zero warning. Once they get to that stage you have to basically slow down and suck it up for the rest of the race. They don't come back after that point. When I say slow down I mean 1-2 seconds off the original pace.

As an aside, I bought my first new set of Hoosiers this year (discontinued RS05's) and I am shocked at how good they are.
[/b]


When you've run old tires for so long and go to a "new" set you ahve to be careful. The first time I did that I almost put the car on its roof because I turned in, and so did the car, just a little earlier then I was use to.