Modern tyre compounds simply don't degrade with heat-cycling. Even the softest racing slicks might be only ones needing warmers. Certainly not street or DOT-R tyres. All staff and instructors at all trackday groups i go to run anything from touring tyres to race-slicks and none of them use warmers.
Afm199 (Ernie) is one of best instructors out there with +50yrs experience. He grabbed me last year to work on some corners @ Thunderhill West. With cords showing on his un-warmed slicks, I still couldn't keep up with him.
http://bayarearidersforum.com/forums...d.php?t=518735
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