re01-r>rt615... if you want the best out of a street tire the top two choices are the re01-r or the neova. rt615 or r-s2 are awesome for the money if your on a budget.

 

Just wanted to report my findings of the RE050A PP on the track at Homestead Miami Speedway this past weekend. Tire size is 225/40/18 and 265/35/18 on BBS LMs. The tires exhibited grip levels comparable to the Mich PS2's I ran previous to these and are much cheaper. Both tires however do go away if you abuse them, I found that trailbraking and powering out of a corner with a bit of slip angle makes them go away in ~5 laps. Once they start going they will squeal and give plenty of notice.

Overall I'm very impressed, for significantly less money than the Michelins these Bridgestones performed just as well. The question is, how long will they last?

 

What tire pressures are you guys running?

I have found that the so called "greasy" tires is, most of the times, a significant reduction of the contact patch due to tire overheating, raising the pressure significantly.

Best way to cure this, is investing in a tire pyrometer and finding the optimal "hot" tire pressure. You'll be surprised on how much air you will have to leak out of your tires after you do that.

 

32 all around hot. The tires would only get "greasy" after abusing them for a lap, if you're easy on them and keep the sliding to a minimum they stay grippy. I don't think it would be a good idea to bleed the pressure to a level where the tire would grip at its greasy stage because when you're not abusing them they probably roll.

 

How did you come up with that number (32 psi hot)?

You NEED two tools to optimize your tire pressure at the track: tire pressure gauge and a tire pyrometer.

That will allow you to know two things. Adequate camber and adequate tire pressure.

If you haven't used that method to come to that number, you cannot claim the tire got greasy. They could've easily just gotten too hot.

I don't know what you mean by "abusing" the tire, either. Driving on the optimal slip angle as much as you can does not mean abusing the tire. It means maximizing its grip potential.

Obviously sliding the tire means more heat generation, so your pressures may go up significantly at that point, giving you the false sensation of having "greasy" tires.

 

It's the baseline that I start with. I go out at 32 cold, come in, bleed down to 32, go out, bleed down to 32 again, and check to make sure I've reached the ceiling where the pressure stops increasing. After two bleeds the pressure levels off at 32 once I warm the tires up.

[QUOTE]You NEED two tools to optimize your tire pressure at the track: tire pressure gauge and a tire pyrometer.

 

I just purchased some Re01r's. I will report my findings. I agree with the posted above about my way of checking my pressures. I do not use a pyrometer. Just a tire gauge and I check the psi cold and hot and maintain anywhere from 30-34 depending on conditions. This is a street/track car and until I have a garage, street/track tires will be used.

 

Well, you still haven't answer my question on how you decided that 32 psi is the best hot pressure for the RE 01R on the s2000.

Don't get me wrong. Tires do get greasy. But that's uncommon. Overinflating, is common. Despite popular belief, you do want some roll.

I used to use the tire chalk technique too, from what everybody says, and from what I read on the Internet.

Until I went to a seminar about tires run by Michelin engineers. First thing they did, was to throw away those internet myths. We even took our cars to the track and they would wait for you to come in after hot laps to fine tune your tire pressures.

You won't believe how overinflated the tires were using the chalk technique. And I'm not talking about me only. I'm talking about most of the instructors that were attending this seminar.

Since I bought a pyrometer, I haven't had greasy tires anymore.

I usually use R-compound tires, but when I use street tires, using the same technique has minimized that problem big time. In fact, my pressures are almost 4 psi lower than what the internet consensus dictates for my car and tires.

I'm not saying you are wrong. I'm saying the technique you may be using to optimize your tire pressure may not be adequate enough.

Just enough to say, that every student I had, and used my tire pyrometer to adjust their tire pressures, ended up with significantly lower tire pressures than they thought they needed. And they all agreed that it made a tremendous difference in traction and consistency.

Give it a try. It will make you safer. Whether you are racing or not, it will make your runs safer.

 

nice! - RT615s =

 

I'm running RE050A Pole Positions, not RE-01R. I have no doubt that the pyrometer method is more accurate but I don't think there's anything wrong with the chalk method. Regarding your example, I don't understand the usefulness of a pyrometer once the tire pressure stabilizes at X psi....

There is none, that is the maximum the air will expand.