This is the tire heated and broken by wire heater . Logically saying, wire heater heat only the place where directly contact to the tire, and need to wait for heat transfering to entire the tire. You may think it has thermostat inside, and will control the temperature. If it is correct, It does not burn tire as in the picture. Maybe you think this tire warmer is broken. No,,, It is not broken. Thermostat measure actual tire temperature. Heating wire heats higher and higher until tire temperature rise up to 194℉. Actual wire temperature would be more than 248℉．　As a result, tires would be broken before race by using tirewarmers which was supposed to make tires to be good for race.
 
 The tirewarmer is burnt and the heating wire is exposed. If the heating wire is properly temperature controlled by a thermostat, this will not happen.
The thermostat does not sense the temperature of the heeating wire, but the temperature of the tire, so it is proof that the temperature of the hot wire has risen excessively and burned the fabric
 
 
   
 
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