I thought you WERE speaking to 'some one who's thought about it'.......
..... and you are talking about 'hysteresis'.....
I'll be happy with your answers IF YOU can deliver 2 items of information.
1) Your current explanation of 'ideal retardation' can be 'codified' (crudely)as: "Ideal retardation occuirs when, at 100kph, the tyre 'slipping' at a 20% rate". That would mean the tyre was 'skidding' at 20kph compared to the road. Let's simplify this discussion by encoding that as 'speed/slip' thus 100/20. Let's not argue that 15% or 25% 'slip' might be better, we'll just use 20% as a convenient figure.
So, I need you to tell me what, at the level of the contact patch, what it experiences DIFFERENTLY at 100/20 to that which it experiences at 50/20 where that slip rate is now, not 20%, but FORTY percent.
It's not that I am claiming there ARE no differences...... I am just trying to get you to the point of realising the ONLY difference is the RATE OF REPLACEMENT of the contact patch! Once you've arrived at that point........ I am suggesting that ABOVE 20% slip, the contact patch OVER HEATS. AT 20% slip, it heast the tyre contact patch to the IDEAL temp, and BELOW 20%, it UNDER HEATS the contact patch!
That explanation covers WHY each type of tyre requires a DIFFERENT degree of 'slip'. The video posted for Rob shows that Dragsters seem to use about 100% slip and your comment about F3 tyres seems to imply they need about 5%.
Show me where I am WRONG about this (on that SPECIFIC point about HOW the contact patch 'knows' that it's 'suffereing' 100/20 and not 50/20)! There are no OTHER differences from the contact-patch's 'frame of reference' than the REPLACEMENT rate!
2) show me the data on INSTANTANEOUS grip of tyres that are 'skidding' (E.g., 100/0). By this, I mean the amount of 'grip' that is obtained by a tyre in the FIRST (let's guess) 1/10th of a second! Yes.... I FULLY agree that, if the tyre remains LOCKED for 1 or 2 seconds, the grip reduces DRAMATICALLY.....I have just NEVER seen the data for a tyre that DOES NOT REMAIN LOCKED!
I do NOT have 'the figures' and I have only 'worked out' this stuff from YEARS of practice and THOUGHT! I have no PROOF of my conjecture whatsoever..... however, I do have a 'pleasingly plausible' explanation that has NOT been 'eliminated' by DATA, as yet!
You have to remember, we karters have used this technique for FIFTY YEARS to MY PERSONAL knowledge! None of us did it becasue we were TOLKD that it worked.... we did it because we could FEEL that it works! I can see NO mecahnism that allows us to sense and control a 'reduced rotation' rate on the REAR tyres (which we can't SEE while we are driving....) but I CAN find an acceptable explanation of HOW we sense and control the 'jerky semi-lock'. It also fits EVERYTHING that we see and HEAR while WATCHING drivers use it!
Oh.... and if you think THIS is weird..... go and watch QUICK karters who use the 'Scandanavian Slide' into corners (right/left into a LEFT corner). That one makes no CONVENTIONAL sense, either!
Ian
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