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      06-11-2012, 02:48 PM   #1
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To shave my used RA1s or not to shave.....

In preparation for my track day at Laguna Seca on June 30th, I am getting my tires setup. For the past year of track and autocross I have ran shaved 275/35/18 RA1s in the front and full tread 305/35/18 in the back. The setup has been amazing and I was unable to push the tires to their limit at the track. Although I do often push the tires to their limit and beyond at autocross.

So I recently chorded the shaved fronts and am getting pretty low in the back. The backs seem to be a bit more slippery than I remember, but I may have also been pushing them harder than normal at the last autocross. So I picked up a set of fronts that have tread, and now I have 4 unshaven tires. To enhance front grip and refresh the rears life I was thinking about shaving all 4 tires for Laguna Seca. So I was just wondering everyone's thoughts and was also looking for anyone who has experience with full tread RA1s vs shaved. I worry about grip in the front and have contemplated trying 285/30/18s possibly.
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      06-11-2012, 05:36 PM   #2
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Ok, I'm not one to go around correcting spelling/grammar all the time but at least in the track forum we can get this right. Chord = something you play on a guitar Cord = stuff that shows through the rubber on a tire when you've killed it

If I owned a tire shaver I wouldn't shave used tires. Too easy to mess up the blade with rocks and nails and stuff. Shaving won't bring your rears back if they're heat-cycled out, which they might be. Get some formula V or other tire softener and use that if you're worried, probably cheaper than shaving and won't be a waste of time and rubber. I would definitely go to the 285's in front if I were you.
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      06-11-2012, 05:41 PM   #3
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Quote:
Originally Posted by Richbot View Post
Ok, I'm not one to go around correcting spelling/grammar all the time but at least in the track forum we can get this right. Chord = something you play on a guitar

Cord = stuff that shows through the rubber on a tire when you've killed it

If I owned a tire shaver I wouldn't shave used tires. Too easy to mess up the blade with rocks and nails and stuff. Shaving won't bring your rears back if they're heat-cycled out, which they might be. Get some formula V or other tire softener and use that if you're worried, probably cheaper than shaving and won't be a waste of time and rubber
Cord hahahahah

And I would be getting them shaved through a shop that specializes in race prepping. And they do have an expensive shaving machine.
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      06-11-2012, 05:44 PM   #4
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Have you asked them if they will shave used tires for you? It's possible, it's just a PITA to check the tires for stones and other crap in the tread before shaving

http://www.racerpartswholesale.com/p..._Strengtheners
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      06-11-2012, 08:31 PM   #5
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Quote:
Originally Posted by Richbot View Post
Have you asked them if they will shave used tires for you? It's possible, it's just a PITA to check the tires for stones and other crap in the tread before shaving

http://www.racerpartswholesale.com/p..._Strengtheners
Interesting, I've seen ads for that stuff in GRM and other places and always kinda suspected it was a gimmick. Do you have experience with it? What compounds does it improve? (I was guessing it couldn't save true slicks that had 20 HC's and would be pointless on normal street tires?)

OP: I wouldn't shave used tires. In my experience RA1's got fastest right before cording though, don't remember heat cycles being an issue.
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      06-13-2012, 02:09 PM   #6
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I've run full tread depth and shaved RA-1s on my e36m3 race car (sold). Full tread depth are fine, as long as you don't push them very much. I would recommend getting the new ones shaved slightly (2/32nds or so) at a minimum, or do a lot of highway miles with them. I chunked a new RA-1 at Phoenix at PIR. Too much for the right front on the banking. Laguna won't be kind to the right front either...

I agree with Porschefile. My fastest times on RA-1s occurred in the session I corded them.
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      06-15-2012, 03:47 AM   #7
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Quote:
Originally Posted by admranger View Post
I've run full tread depth and shaved RA-1s on my e36m3 race car (sold). Full tread depth are fine, as long as you don't push them very much. I would recommend getting the new ones shaved slightly (2/32nds or so) at a minimum, or do a lot of highway miles with them. I chunked a new RA-1 at Phoenix at PIR. Too much for the right front on the banking. Laguna won't be kind to the right front either...

I agree with Porschefile. My fastest times on RA-1s occurred in the session I corded them.
I push my fronts really hard. This is making me want to order some 285/30/18 R888s shaved and call it a day.
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      06-15-2012, 07:27 AM   #8
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That's what I would do. Full-tread RA1's kinda suck in the dry if you're a decent driver.
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