There gas been a great deal of discussion about the RPM's of the ICE. The context of this has revolved around the Angry Bees, but also at other times when the engine is running with no apparent rhyme or reason. Some have gone so far as to quote numbers (ie: sounds like 5,000 RPM's) when the reality is that nobody's ear is calibrated enough to really render a useful quantitative measurement. Today, I decided to attempt to answer this burning question. I connected an OBD2 scanner to the car, and set out on a ~30 minute journey. I chose this trip specifically such that I was in EV mode for approximately 1/2 of the trip, at which point I knew the EV miles would reach zero, and I would be on gas for the remainder. To my delight, the OBD2 port does report the RPM's of the ICE. It is of course zero when you are entirely electric. When you transition to 'hybrid' mode, then the ICE continually cycles on and off depending on the terrain and your demand. Here is a graph that shows the vehicle speed and the ICE RPM's throughout this 30 minute trip: Note that at around 950 seconds, the EV miles reached zero, and the ICE began to operate. It ran at a steady 1500 RPM's, and then up to 1800 or-so for another stretch. We stopped for a few minutes (to get gas), and started up again at around 1200 seconds. In order to see the detail a little better, here is a plot that zooms in from 1200 to 1500 seconds: The ICE seems to 'like' running at ~2000 RPM's with some variation between 1200 and 2300. I did try briefly going into HV-Charge mode (the last spike on the blue curve on Plot 1. HV-Charge just seemed to run at a very steady 2000 RPM. As expected, the engine RPM's do not correlate to the vehicle speed (ie: not the normal transmission behavior since the engine is charging rather than driving the wheels). Note - This my first look at this. It was for one convenient trip. I am sure there can be a lot of variation depending on the driving scenario. What would be of great interest is the behavior with the Angry Bees! I have not experienced the Angry Bees (and I am not sure that I want to)... However, if someone can tell me precisely how to summon the Bees, I may be willing to log a test run in order to put to bed the discussion of what the Bee RPM's actually run. BTW - it is 'easy' to set up to log your RPM's. I used a $10 OBD2 device that communicates with a smart phone via BlueTooth. I used the 'Torque' App which is capable of generating log files, which can be downloaded as a .csv file and plotted with your favorite spreadsheet tool. If someone actually wants to try this, I can provide more details. Although the RPM's are available, I did not find much else that seemed useful. I would love to somehow access the wealth of engineering data that probably exists somewhere, but Honda will never be willing to release details of a diagnostic API (or similar).