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Low-side - Tire choice question

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I was at the track over the memorial day weekend and ended up in a low side. This is my second low side, but the first that was due to an error on my part. (The first time was at COTA when another rider took me out). So let me start by setting the tone for the day. First, the surface of the track is only one season old and lacked grip up until the end of last season and even then, I struggled with more sliding than I prefer. It was a hot/humid start with temps already in the mid 80's at 8 am. I rode the first session on my R3 and then switched to my RSV4 for the second. The RSV4 had brand new Dunlop N-Techs (Soft front and rear) I had chosen the softer compound to see if it helped with a bit more traction on this new-ish surface.  I was throwing down really good times, especially considering it was my first time back at this track since last season and I was already running the same times I was running at the end of last year. At the end of that session, I was pumped at how great the bike was feeling with the tires. I was however, already feeling some of the effects of some dehydration so I upped my fluids/salts. Went out for the 3rd session.It was now 91 degrees (not counting heat index) and I was running a full second off from the previous session. Came around to T10 on my 4th hot lap, this is a corner I had been progressively taking a bit faster. I entered the corner and the next thing I knew the front end tucked and I was sliding off the track. I had zero feedback from the front end before/when this happened.

Did I trail brake too much? Did I make a mid corner correction while already near/at max lean? Did the choice of a soft front compromise my front end traction? Was it a combo of 2 or more of these? 

I truly think it was a subtle mid-corner correction, whose impact was greater due to the increased speeds and lean. Which brings me to what is probably my actual question... can anyone help me rule out the soft compound having had any effect on my traction considering the conditions?  Would the super smooth surface of the track and high temps possibly lower the threshold that led to the low side? I'm now a bit apprehensive to keep the soft up front and thinking about sticking with soft in the rear and going medium up front for the next 3-4 days that I will have at that track this season.

 

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Can you describe T10 (camber, elevation change, etc)? Also, why you chose this corner for making up time?

What phase of cornering were you in where you lost front end feeling? You describe a situation where you were still on the brakes, yet leaned over and still steering. What else were you doing? How tight were you on the bars?

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It’s a fast (60-70mph), relatively open, left hand turn with No perceivable camber change. The crash occurred before the apex. I’m 99% certain I was entirely off the brakes. I was more “thinking” out loud as I typed. If there was any brake pressure, it had to minuscule at that point. As far as the steering input, I’m not even certain that’s a fact, however it’s the only thing that I can think of that would have put me down so fast so I’m making somewhat of an assumption.  I suffered a symptomatic concussion and not sure if that’s why my memory of what actually happened is so broken or if it’s merely the adrenaline. I also don’t want to be that guy that blames an error solely on my tire choice.... LOL

I had a less experienced, fast rider in my paddock suggest that my skid marks looked a little “inside” of his line. Which is what led me to think that maybe I realized this and for some reason added a little lean to maintain my apex vs letting the “ideal” apex go and just riding it out as I set it up. 

Dunno if all that rambling is useful!

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Couple of questions:

1) To clarify, when you say you had "zero feedback" do you mean there was no warning, nothing felt different about that corner in that lap versus the others? Or do you mean the front end felt vague or disconnected right from the beginning during that corner on that lap?

2) You mentioned high temperatures and a fast pace, did you look at the tire after the crash, or have a tire guy look at it? I'm wondering if there is any chance it had gotten really hot, melted on the edge and you leaned it over farther and got onto some melted rubber?

3) You mentioned dehydration and HOT temperatures, any chance there was some tension on the bar due to fatigue?

4) It sounds like you went faster and felt better on the softer tire, which would support using that compound again.... but will you have attention on the tire, worrying about grip or feedback? Would you feel more confident on the previous compound? 

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7 hours ago, Hotfoot said:

Couple of questions:

1) To clarify, when you say you had "zero feedback" do you mean there was no warning, nothing felt different about that corner in that lap versus the others? Or do you mean the front end felt vague or disconnected right from the beginning during that corner on that lap?

- the first one :) I didn’t feel like there was any “warning”. I’ve pushed the front end before so I’m familiar with that sensation but nothing like that this time.

2) You mentioned high temperatures and a fast pace, did you look at the tire after the crash, or have a tire guy look at it? I'm wondering if there is any chance it had gotten really hot, melted on the edge and you leaned it over farther and got onto some melted rubber?

I did not have anyone on hand to take a look. It looked pretty regular to me considering my somewhat limited experience. Since the re-pave, this  track does not wear tires like any other I’ve been on. My tires hardly build up any of those little rubber balls. I digress... LOL

3) You mentioned dehydration and HOT temperatures, any chance there was some tension on the bar due to fatigue?

- absolutely possible. The first two laps that session I was fighting a little cramp in my left calf.

4) It sounds like you went faster and felt better on the softer tire, which would support using that compound again.... but will you have attention on the tire, worrying about grip or feedback? Would you feel more confident on the previous compound? 

- the new compound and traction definitely helped my confidence. As far as grabbing my attention on future rides, I honestly don’t know if it will haunt me. 

I’ve posted on our local page to see if anyone has footage showing the location of my skid marks in the turn. Too bad the guy behind me through the turn wasn’t running a GoPro. He stopped by my garage to chat. He stated that he was surprised to see me go down in front of him. He also followed me off the track. LOL #targetfixation

 

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