So, I recently watched a video by the Brick Experiment Channel about building a 1 Googol:1 reduction gearbox, which at the time of writing this question, is at #44 on Youtube Trending. At the end of the video, it makes the claim that the final gear will rotate once every 10^93 years. This seems unlikely to me; it seems much more likely that energy losses due to friction along the mass of gears will reduce the amount of energy it's receiving to 0, so it will never spin on it axis, at least as a result of this machine.
However, I'm left wondering where exactly this in the contraption energy is lost, and how much of it is lost to heat and how much is lost to noise. How efficient are LEGO Technic gears, when mounted on their standard X-shaped axles through the holes in standard LEGO Technic bricks?