I purchased a Indoor Outdoor Thermometer Digital Hygrometer Temperature Humidity Monitor with Remote Temperature Sensor. I put the sensor in the bin an hour ago and it is currently reading 68 degrees F. I would have expected it would be much warmer. The bin has been full and sitting in my 68 degree kitchen for 2 weeks.
As Bokashi composting is a fermentation process, no heat is being created. The inside of your bin will therefore be at the same temperature as whatever the outside ambient temperature is. 70 to 75 degrees Fahrenheit (around room temperature) is ideal. So with Bokashi composting, monitoring temperature changes is not important, nor a necessary part of the process. The best way to tell if your bokashi composting is working correctly is to use your nose; a sweet pickly smell tells you that everything is fine.