Shaved and Heat Cycled R-Tires

[davidpertuz at mindspring.com]

>I've always used street tires on the track, and I have never chunked a
>tire. Would this have any correlation to the likelihood of me chunking
>an R compound tire such as the Kuhmo Victoracer V700? In other words,
>is it easier to chunk a high performance street tire or an R compound
>tire (unshaved)?

You'll probably chunk a high-performance street tire before you chunk a
DOT-legal R-compound tire. It doesn't surprise me that you've never
chunked a street tire on your car, though - Sentras don't weigh a lot, don't
have tons of power, and I suspect driving style has a significant effect on
the likelihood of chunking, too.

Below is from another enigneer I work with who races an IT CRX on
DOT-legal HoosierR3S03s:
****************
To heat cycle them I generally heat cycle them in a qualifying session
(which is generally 7 to 8 laps), it is probably a little more aggressive that
I should but generally there aren't any practice sessions. After the sessions
I let the air out of them (to cool them down faster) and then let them sit for
a week before I use them.

Sometimes I don't heat cycle them and just run them for the weekend. I
can't say that heat cycling them makes them last longer or work better.

The Hoosiers are good for 8 to 10 heat cycles and then they good for a
couple laps (I can use them for qualifying but I need to have a good lap by
the 2nd or 3rd lap)  but they will go away during a race. Generally I will
wear them out by then unless  I am running a smooth track like MidOhio
or Road Atlanta.

The Hooisers reps all say heat cycling the tires makes them last longer. I
don't try to heat cycle the tires on the rear because it takes too long to get
heat into relative to the front tires.
****************
David