There is a better tool to use for the temperature monitoring assuming you don't have a radio with telemetry feedback.
http://www3.towerhobbies.com/cgi-bin...&I=LXHUH3&P=ML This little guy from Venom (other companies also make them) has a probe that will wrap around the motor or tank or whatever you need to monitor. It's pretty small as well and light as well.