RA1 blowout

#1

Those are inner cords hanging out of that tire.
First time I’ve seen an RA1 complete blowout.

[attachment=1614]RA1blowout.jpg[/attachment]

#2

do you know what led to that? e.g. flat spotted?
thanks,
bruce

#3

2011build? Jeremy and I spoke with a toyo engineer at nationals I’ll post more of that conversation when I’m at areal computer

#4

We mainly wanted to talk to the engineer concerning the 2011 build Toyo’s because they seemed noticeable different than older 2010 and 2009 tires and we were pretty convinced the compound had changed. First they were visually very different, Jeremy has a picture somewhere but it was a freshly shaved older tire vs a freshly shaved 2011 tire. The 2011 tires have a very shiny apperance, very different to the dull texture of the older tires. The engineer thought it could have been the time on the shelf but they were so different that I doubt it. I also have a brand new 2011 set that has been on the shelf for quite some time and they are still as shiny as when I bought them. Also he did say that there was a problem with some of the 2011 tires with them cording prematurely. You can see this on the pictures of my tires below. These tires are from Nationals and were heat cycled at a prior event and they only run for 1 qualifying session and the 2 short qualifying races. You’ll see they are already starting to show the steel belt on the edge of the tire. Apparently this problem has been addressed. But there still remains the problem of the compound. He unfortunately is not privy to all the information from Japan but has been assured the compound has not changed. Although we are not the only group complaining. Apparently the Spec 944 guys have also complained and said they don’t want to switch tires they just want the old RA1’s back. Also notice had badly my tires are grained. The pictures are of the LF and LR tires. In the past I have grained the left front at Mid Ohio as it pushes the left front pretty bad at that track, but I have never ever grained any of the rears and I’ve also never seen a LF grained this bad. Also of note I used to never even bother heat cycling the tires whereas this set is graining terribly and I actually tried to break it in properly.

Left Rear

Left Rear cording

Left Front

Left Front cording

Left Front Graining close up

I had a set of older tires for Nationals (started as 4/32 had 4 races and about 15 heat cycles on them). I ran them in practice and they were better, more consistent and did not grain at all. I was going to run them in the championship race before it rained. Hopefully Toyo got the message and are trying to get things sorted out but the 2011 is not a great tire. It is slower than the older tire and seems to overheat much more easily. Unfortunately I think the U.S. engineers have their hands tied somewhat by what Japan gives them in the way of tires and information. If the tires don’t improve in the next year I would be in favor of switching tires.

#5

The RA1 tires are not going to get better. They use a different compound now, confirmed by recently retired Toyo Engineer. Japan outlawed some of the chemicals.

We have talked about this in previous threads. Either we get to deal with it, or let’s switch. I figure we are not switching because Toyo is the title sponsor. The tire is not the RA1 we all knew and loved, or at least liked.

You don’t have to be a chemical engineer to see and know the difference.

The current RA1:

Wears out sooner
Grains
Groove of Death
Heat cycles out
Takes 4-6 HC to get decent, then goes away
Wears unevenly around the tire

Witnessed consistently on:
Miatas
E30s
944s
Hondas

#6

[quote=“leggwork” post=60064]do you know what led to that? e.g. flat spotted?
thanks,
bruce[/quote]

Don’t know what caused the delamination but the blow out was at the center of the tire after a layer came off. The owner said it was an old tire so I’m pretty sure it was not a 2011 tire.

#7

[quote=“Elephant4” post=60071]We mainly wanted to talk to the engineer concerning the 2011 build Toyo’s because they seemed noticeable different than older 2010 and 2009 tires and we were pretty convinced the compound had changed.[/quote]There is a ton of anecdotal evidence that the compound changed.

Regardless of the compound change, those photos look like evidence of setup problems to me. Or overdriving the tires.

Any tire will grain like that if you don’t get it warmed up and if you slide it more than it likes.

PS - Notice I didn’t say anything about you needing a s------r? :woohoo:

#8

PPS - Here’s some interesting reading for those who want to know more about what causes graining. Learn Me Some Graining

#9

FWIW, I don’t typically over drive my tires (I don’t go that fast!), but I did see significant graining on my 1-heat cycle, properly broken-in, RA-1s at Mid-O.

#10

My driving and setup hasn’t changed, so that just leaves the tire.

#11

I’m not debating if the tire has changed. Your sentence identifies 3 things that can be changed. The tire will be the hardest one to change.

#12

I need a splitter :stuck_out_tongue:

#13

I need a splitter :P[/quote]It only took me 132 posts to get you to admit it. :woohoo: Like I offered before, $20 and I’ll send you a copy of my template. B)

#14

I need a splitter :P[/quote]It only took me 132 posts to get you to admit it. :woohoo: Like I offered before, $20 and I’ll send you a copy of my template. B)[/quote]

Haha yesssssss. I’ve made a bunch of these things. I can give you a blank Simon. Just attach it to some sort of lip so it’s low enough to be effective.

#15

[quote=“cbullard” post=60107][quote=“Steve D” post=60099]
I need a splitter :P[/quote]It only took me 132 posts to get you to admit it. :woohoo: Like I offered before, $20 and I’ll send you a copy of my template. B)[/quote]

Haha yesssssss. I’ve made a bunch of these things. I can give you a blank Simon. Just attach it to some sort of lip so it’s low enough to be effective.[/quote]

Thanks guys, I’ll wait to see if its still legal next year before I do anything.

#16

[quote=“csrow” post=60059]Those are inner cords hanging out of that tire.
First time I’ve seen an RA1 complete blowout.

[attachment=1614]RA1blowout.jpg[/attachment][/quote]

I just saw a miata yesterday, same style of blowout at Infineon.