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From: xxx <xxx@ToyoTires.com>
Date: Mon 11:02 AM
Subject: racing tire info
To: xxx@xxx.com
CC: toyotech <toyotech@ToyoTires.com>

The optimum performance temperature range for the RA-1 is about 80-100
degrees Celsius (or 175 to 212 degrees Fahrenheit). Because the tires
will cool when taking temperature, your readings should be somewhat below
what I have listed above. If they are equal or higher, you
are running too hot.

Remember that these are simply the optimum temperatures for the
compound. Based on track conditions, you may not be able to reach these
temperatures (such as on a wet or cold day), and on an extremely
hot day, it may be very easy to reach and go over them.

For true racing applications, shaving is always recommended for dry
conditions. Full tread depth should only be used for wet conditions.
As far as heat cycling, this process is really not necessary for the RA-1.

I am aware that other manufacturers do recommend their race tires to be heat
cycled. The RA-1 compound is fairly durable and tends to be less sensitive
with regards to how the number of heat cycles put on a set affects
performance. As long as you shave the tires (usually down to 4/32")
for hard racing use, you should be fine.

I hope this information helps.

xxx xxxx
Staff Engineer
Technical Service Dept.
Toyo Tire (U.S.A.) Corp.

--------------------------------------------
Other info:

Operating Temperature:
- 160 F to 220 F

Target Hot Inflation Pressure:
- High 30's to Low 40's (PSI)

Recommended Camber:
- 2.0 degrees to -5.0 degrees

Maximize Tire Life:
- The degree of negative camber required to get the most performance out of
the RA1 can often lead to inside shoulder wear.

- To maximize tire life, the tire should be dismounted from the wheel and
flipped (move inside shoulder to the outside) when the tire is about half
way worn.

Directional Tread:
- The directional nature of the RA1 tread pattern is only applicable for wet
conditions to optimize water drainage. If they are being used in dry
conditions, the direction of rotation does not matter.