The Lego Technic set 42140 App-Controlled Transformation Vehicle introduces two new gears - a flat version of the 12 tooth bevel gear and a flat version of the 20 tooth bevel gear. These gears are designed to have less friction. In this video I measure the difference in gearing efficiency between two gearboxes - one made from a stack of 3 of the original 12 and 20 tooth gears to create a 27 to 125 gearing ratio, and a similar version made from the new flat 12 and 20 tooth gears. The gear box losses are measured using a powered up motor and a powered up App to determined the efficiency of each gear box by lifting different weights. The results are presented and compared for each gearbox.