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I didn't follow up enough with the other guys to know how things fared as far as shaved versus unshaved.  A lot of what I'm seeing on other forums and the like is that it doesn't seem to make much of a difference at all.  One guy that is running them one his Tour event on them unshaved and a few weeks later did it at another event shaved.  I'll probably not know more about what people are doing or not doing until the end of June as far as what is working locally. I plan to stay unshaved and our other 318 is getting tires today as well and also going unshaved.

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Steve Nackers

R Street index HS. #723R
'98 BMW 318i
www.nsnmotorsports.com

And some news on the R1R today. My sources tell me the following sizes were released today:

205/50R15
205/55R16
205/50R16
205/45R16
235/45R17
245/40R17
275/40R17

Ian
 

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--CRX Addict
--Recovered Mini Addict

ibaker:

And some news on the R1R today. My sources tell me the following sizes were released today:

205/50R15
205/55R16
205/50R16
205/45R16
235/45R17
245/40R17
275/40R17

Ian
 

Specs?  

--Andy

 

I swear the tire manufacturers of the world take pleasure in torturing STS/STS2 competitors by releasing every size they can possibly think of except the 225's that are what we really want. It's like a contest to see if they can force you to by the tires you really don't want......whatever....getting so I don't even want to follow this thread anymore. Just give me my trusty 205 Bridgestones and the heck with Toyo's, Kumho's & Dunlops until they come with a decidedly better tire due to compound, size or both.

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STS class '96 Saturn SC-2

I also got tired of playing the Toyo waiting game and mounted some Bridgestones this past weekend.

Gunny JC:

I swear the tire manufacturers of the world take pleasure in torturing STS/STS2 competitors by releasing every size they can possibly think of except the 225's that are what we really want.

Or...it's not all about us.  Instead, it's all about the general market that buys way more tires than we do.

I know it's hard to imagine, but we are not really the center of the universe for tire companies, regardless of what some of the marketing departments would have you think.  Heck, we aren't even the center of race-specific Hoosier's universe, although we are at least a decent-sized star in it.  Relative to someone like Toyo, our market is a lowly asteroid in some obscure solar system ...

--Andy 

Andy Hollis:

Or...it's not all about us.  Instead, it's all about the general market that buys way more tires than we do.

Looking at the info I got, part of the info released with the new sizes was what vehicles they fit and whether it was an OE or Plus size fitting. interestingly enough, all the sizes just released with the exception of the 205/50R15 and 245/40R17 were OE sizes, and the 205/50R15 and 245/40R17 were listed as a plus size. What it shows is that they are trying to get OE sizes out first and after that I'm sure they will start on the ++ sizes. After all, how many cars, if any, came with a 225/45R15 stock?

And now the rest of the juicy details:

Size                 OAD    OAW    Rim (min-measured-max)
205/50R15 86V    23    8.5    5.5-6.5-7.5
205/55R16 91V    24.8    8.1    5.5-6.5-7.5
205/50R16 87V    24.3    8.4    5.5-6.5-7.5
205/45R16 83W    23.2    8.1    6.5-7.0-7.5
235/45R17 94W    25.3    9.4    7.5-8.0-9.0
245/40ZR17 91W    24.7    9.8    8.0-8.5-9.5
275/40ZR17 98W    25.6    10.8    9.0-9.5-11.0

Ian

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--CRX Addict
--Recovered Mini Addict

I mounted up some R1R 205/45-16 tires today, shaved to 3/32nds.  Will see how they work this weekend.  :)  

 Pic below = 205/45-16 at 3/32nds, 195/50-15 at full tread, and another 205/45-16 at 3/32nds  

 

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89/189 STS/STX '89 Civic Si

BrianGT:

I mounted up some R1R 205/45-16 tires today, shaved to 3/32nds.  Will see how they work this weekend.  :)  

 

Tread width measurement?

--Andy 

Damn Brian, I thought that the amount of tires in my garage has gotten silly.  You look like to have a tire warehouse there!  It is awesome!

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Mark Davis
1993 Toyota MR-2 White "Casper"

TurfBurn:

Don't forget about the Dunlop Direzza Z1 * Spec.  Early results show them stacking up well/better than the RE-01R's and the wear is very good.  I ran this past weekends event on them at full tread depth and a number of other competitors did as well and some had them shaved. I had no chunking or wear issues at full depth, and was very pleased with the results.  The other competitors were also very happy with them.  Definiltey think it'll be a tire that is showing up a lot this year.

 

EDIT:  I'm not saying the Direzza is necessarily "THE" tire to go with... I think the RE-01R is still a top tire.  But just wanted to clarify/mention that it isn't as simple as RE-01R versus Toyo R1R for tire choice.  And that the Direzza is a longer wearing tire (likely similar in longevity to the RE-01R) and very affordable.

here's a data point on the Z1 Star Spec [195/55-15] unshaven

i was trying to work out tire pressures versus under/oversteer this morning on the Cooper - collecting data using the poor man's DL1 (GTech RR)

Cooper S, H&R Coil overs, -2.5 front, -1.0 rear

47 degrees air, 50 degrees surface - asphalt

37psi front, 42psi rear

max lateral grip 1.03g

front tire surface temp only reached 90f, so presumably there are a few more tenths to be had with more heat...

for reference, the 225/45-15 Kook RS2 returned 1.06 to 1.09 last year under optimal conditions (25 degrees warmer)

transition control is good, and exit grip also good - the overall feel inspires confidence due to controllability

not bad for a 6 3/8" wide contact patch, but I still wish for a 225 or at least a 205 in one of the good compounds...

ah well, they'll be fine for the region and i shall have to purchase another set mid summer when the wider tires are released and evaluated

I reckon the Z1 could be lovely for the 2,050 pound STS folks, but this is a 2,500 pound 200hp STX car...

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Charlie Thompson
'04 JCW Cooper [STX]
NER Cannon Fodder

Andy Hollis:

BrianGT:

I mounted up some R1R 205/45-16 tires today, shaved to 3/32nds.  Will see how they work this weekend.  :)  

 

Tread width measurement?

--Andy 

The 205/45-16 is ~1/8" wider than the 195/50-15.  Here is a picture of a stack of toyos next to a stack of bstones, 2x195/50-15 shaved on the bottom, and 2x205/45-16 on top on 16x7.5.  The 15" are full tread, and the 16" are shaved.

We were going to try to get some comparisons on Glagola's car vs his 15" toyos, but it rained on Sunday, so afternoon time-only runs were cancelled.   We will try to get some objective testing over the next 2 weekends.  I now have some 15x7.5" rotas and 6 more 15" wheels, so I will see if I can get some 205/50-15 tires also. 

 -Brian
 

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89/189 STS/STX '89 Civic Si

BrianGT:

I mounted up some R1R 205/45-16 tires today, shaved to 3/32nds.  Will see how they work this weekend.  :)  

I'll have a set of the 205/50-15's mounted next week and will be doing some testing that weekend. I'll be running the 195/50-15 RE-01R's and the 205/50-15 R1R's back to back and we will see how they do. Both will be shaved to 2-3/32's and hopefully both will be on 15x7 RPF1's. I may switch the R1R's to a set of 15x7.5's if they are really wide.

I'll let everyone know how the testing goes.

thx

Ian

 

 

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--CRX Addict
--Recovered Mini Addict

Have you ever driven on the Toyos?  If not, be prepared for some weirdness.  They take some getting used to in both driving style and car set up.  I'm not sure a fair test can be conducted without optimizing the car's suspension and alignment tune.

I'm going to look at the 205/50-15, 205/45-16, and the 195/50-15 after work today.  I'll decide which one I want to buy next at that point.  I like the 195s a lot so it's going to be tough.

I measured the tires today for circumference, and calculated the diameter of the R1Rs:

195/50-15 - minimal tread left = 22.75" diameter
195/50-15 - almost full tread = 23.0"
205/45-16 - 3/32 tread = 23.0"

I used a string method, and the full tread 195 marks matched up exactly to the marks on the 16" shaved to 3/32nds.

As for weight of the R1Rs:
195/50-15 minimal tread on 15x7 rpf1 = 25.8 lbs
195/50-15 full tread on 15x7 rpf1 = 29.4 lbs
205/45-16 3/32 tread on 16x7.5 ssr = 29.4 lbs

It was very strange the the full tread 195/50-15 was exactly the same diameter and weight as the 3/32 205/45-16.  I checked them multiple times.

Compared to the Bridgestones:
195/50-15 RE-01R almost full tread on 15x6.5 konig helium = 32.4 lbs
205/45-16 RE-01R 2/32nd tread on 16x7.5 = 30.2 lbs

R1R Tread width:
~8" for 205/45-16 R1R on a 16x7.5" and ~7 7/8" for 195/50-15 R1R on a 15x7" (measurements = +/- 1/16" depending on how you judge treadwidth, but the relative to the 15" 16" is 1/8" wider.  I am measuring with a string, so I don't think a wider 15" wheel will make a huge difference)

-Brian 

 

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89/189 STS/STX '89 Civic Si

Good post.

glagola1:

Have you ever driven on the Toyos?  If not, be prepared for some weirdness.  They take some getting used to in both driving style and car set up.  I'm not sure a fair test can be conducted without optimizing the car's suspension and alignment tune.

I'm going to look at the 205/50-15, 205/45-16, and the 195/50-15 after work today.  I'll decide which one I want to buy next at that point.  I like the 195s a lot so it's going to be tough.

Yah, I'm curious how the rear camber setup I run will affect the changeover. I'll have a good bit of time to play with stuff during the day and I'll bring extra springs, bars, etc with me but hopefully I won't need to resort to that. I think a bit more rear camber will help the car rotate earlier and provide the same mid corner contact patch (hopefully the extra lateral G's cause extra roll, which takes up the extra camber, etc, etc). Worst case I bump the rear rates about 50lbs and see how it works.

I'll do 2 sets of runs, the first in the AM with the bridgestones followed by a couple runs with the Toyo's. The car will be set up for bridgestones at that time so that will be a good initial test. During lunch I'll make any changes I feel are needed to optimize the car for the Toyo's and run another set of runs in the afternoon but with the Toyo's first and the bridgestones second.

Should be fun :)

Ian

 

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--CRX Addict
--Recovered Mini Addict

Agreed, except that there's a 1/2" difference on wheel widths. How much of a change could that give in overall width? Would the 195 be just as wide on a 7.5" as the 205?

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Andrew
STS2 114 - 1992 Miata

amaff:

Agreed, except that there's a 1/2" difference on wheel widths. How much of a change could that give in overall width? Would the 195 be just as wide on a 7.5" as the 205?

I measured the contour of the tread with a string, so that should fully account for the tread width.  The .5" wider wheel should flatten out the contact patch a little bit though.

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89/189 STS/STX '89 Civic Si

I picked up a pair 205/50-15 R1Rs today, and put a pair of 15x7.5 wheels.  They are about 3/8" wider than the 205/45-16 R1Rs.  (~8" vs ~8.375")

Here is a comparison pic.  They are both on 7.5" wheels.

I also picked up a bigger speedway section for the ASR rear swaybar also :)  It is over 5x stiffer than the ST bar, but weighs less.  A-Spec Racing kicks ass :)  pic:
http://www.briangt.com/gallery/sts/sways_bigger_bar
 

My wife is a little pissed at me, and told me that I better bring her a set of fresh tires for her car, before I am allowed to buy any more tires for my car.  Luckily, I have enough to last a while.

 -Brian
 

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89/189 STS/STX '89 Civic Si