72 replies to this topic

[Jim Drago]

I think I am starting to see that as well.

[Ron Alan]

Well, we're there because the tires are heat cycled out after 8 sessions.... This is pretty much what the old SM6/R6 was like so I'm not really surprised. I also noticed the dreaded R888 dip 2" in from the outside of the tire, did you?

Isn't that the norm? Certainly is on the RA1 in our region...the E30's with their extra 400lbs get it really bad

[Charlie Hayes]

The groove of death!!!

[Alberto]

Isn't that the norm? Certainly is on the RA1 in our region...the E30's with their extra 400lbs get it really bad

According to the durometer, that is not my experience but I'm not as fast as Kyle.

[Charlie Hayes]

Alberto, the miata's do not see the groove. We can normally see a pretty even wear pattern on the RA1, though the E30s use about 5in of the available 8in of tread on the RA1. Like mentioned the groove is normally about 2-3 inches in from the outside of the tire.

[philstireservice]

The groove of death!!!

Groove of Doom..........death is a little severe...

[Charlie Hayes]

touche.

[svvs]

Alberto, the miata's do not see the groove. We can normally see a pretty even wear pattern on the RA1, though the E30s use about 5in of the available 8in of tread on the RA1. Like mentioned the groove is normally about 2-3 inches in from the outside of the tire.

Here in the NE I had two sets of RA-1's get that weird groove/dogbone shape. They were bought about the same time though.

Still don't know what I'm running next year, but we'll see.

[granracing]

Yes, suspension spring rate is spec however I was talking about a discussion they had related to the tire psi impacting static spring rates (some information can be found under SAE formula). Their discussion of this went right over my head!

Jim, the shaving questions wasn't like you're thinking. It about someone so used to Toyos and shaving them...

[Alberto]

Alberto, the miata's do not see the groove. We can normally see a pretty even wear pattern on the RA1, though the E30s use about 5in of the available 8in of tread on the RA1. Like mentioned the groove is normally about 2-3 inches in from the outside of the tire.

Charlie,

I was actually referring to the heat cycle comment that Alex and Ron mentioned about heat cycling RA1s in 8 cycles. I had the 6/32 tires I stared the 2011 season with looked at by someone with a durometer and they were still nice and soft and grippy. I used them at the last 2 free Thunderhill test days. Almost done with them.

A

[Ron Alan]

According to the durometer, that is not my experience but I'm not as fast as Kyle.

Whats funny is when the tires come off under heat/pressure, you don't really notice. But when you pull them out for the next weekend...oh man! Of course this is when you are down to 1 line this becomes obvious. I think flipping seams to give you an extra couple heat cycles. Just give yourself one practice session after the flip! Don't expect to qualify on them!

[Charlie Hayes]

Charlie,

I was actually referring to the heat cycle comment that Alex and Ron mentioned about heat cycling RA1s in 8 cycles. I had the 6/32 tires I stared the 2011 season with looked at by someone with a durometer and they were still nice and soft and grippy. I used them at the last 2 free Thunderhill test days. Almost done with them.

A

Thats pretty awesome. The special alignments we do for you help out also.

[Alberto]

Whats funny is when the tires come off under heat/pressure, you don't really notice. But when you pull them out for the next weekend...oh man! Of course this is when you are down to 1 line this becomes obvious. I think flipping seams to give you an extra couple heat cycles. Just give yourself one practice session after the flip! Don't expect to qualify on them!

I bet. I remember it being that way when I raced karts. You'd get to the track and get a slippery surprise if you weren't actively keeping count of heat cycles and had a new set of slicks waiting.

I wish I had known about the tire flipping thing earlier. I flipped my tires the morning of the Infineon race. My second time on that track and first time in the Miata, still learning the racing line and running tires that all of a sudden had no grip. That was the biggest clusterfux of a weekend for me... Glad I made it out in one piece.


Charlie - Yeah, you and Tim @ TFB Performance nailed the alignment and corner balance all year on my car. It was great knowing that the car was solid and well setup at each event that I participated in. Thanks to you guys, I could just get to the track, set pressures and drive - and learn. Thank you both for your help this year. Lots and lots of learning to do...

[granracing]

Okay, so about this flipping the tire. You really think that overcomes the heat cycles? I really don't know. Always driven a harsh FWD car where 4 cycles and back to the rear if I wanted to stay up front.

[philstireservice]

Okay, so about this flipping the tire. You really think that overcomes the heat cycles? I really don't know. Always driven a harsh FWD car where 4 cycles and back to the rear if I wanted to stay up front.

I don't think flipping the tire overcomes a heat cycle. Where it came from on the car and how not worn it is already may have more to do with extending a heat cycle or two. But as it was mentioned before and is true, a heat cycle is a heat cycle, if reaches operating temp and cools to ambient temp - one heat cycle.

[Michael Colangelo]

Cage tubing is at Kessler Enginering's shop and the build will begin soon. You're in SM now John? Very cool. Looking forward to getting my butt handed to me.

No mo' Honda?

That's it, Dave. I'm reporting you to Honda-Tech!


J/k, good luck. BTW, is Kessler in Berlin? I grew up there, haha.

[Keith Novak]

Flipping the tire and heat cycles are two different things.

Rubber in a tire acts like a spring vertically,horizontally, and torsionally (if that's a word). The flex in a spring is affected by both the material properties of the spring, and the length of the spring. Heat cycles change the material properties of the rubber and changes the way it flexes (stiffer spring material). Flipping the tire puts the part of the tire that still has more rubber left in the place that's taking more force (longer spring length).

These two things are working together. Figuring out how to make the two of those work best together, for the longest duration is why there are tire engineers and I'm not one of them.

[Jim Drago]

Jim, the shaving questions wasn't like you're thinking. It about someone so used to Toyos and shaving them...

I know, I was busting your chops.. But shaved Hoosiers are here and will become more visible at bigger races IMO...

[Alberto]

Flipping the tire and heat cycles are two different things.

Rubber in a tire acts like a spring vertically,horizontally, and torsionally (if that's a word). The flex in a spring is affected by both the material properties of the spring, and the length of the spring. Heat cycles change the material properties of the rubber and changes the way it flexes (stiffer spring material). Flipping the tire puts the part of the tire that still has more rubber left in the place that's taking more force (longer spring length).

These two things are working together. Figuring out how to make the two of those work best together, for the longest duration is why there are tire engineers and I'm not one of them.

Interesting. I just did it to even out wear pattern since I started on rain depth tires at 6/32nds.

[guest driver]

I know, I was busting your chops.. But shaved Hoosiers are here and will become more visible at bigger races IMO...

worrying about "torsional spring rates, stiffer flex rates per heat cycles" ... "shaved, waxed, botoxed and contoured" Hoosiers ....
all way over my pay grade.

much rather show up at the Hoo trailer at 7 am, rummage through the stacks inside the trailer, find the sets marked "hold for #2" ... and buy those.
have a stout and a smile ...