Even though I don't know Japanese and doesn't know a lot about tamiya mini 4wd,I really love your videos since it involves science, engineering,fun, creativity and observation.Also your explanation of concepts really rocks! I really like these kind of videos.
The barrel roll exit is flexing down because of the car speed. Probably could put some truss to lessen the flex. That's why the car was launching off the track when it exit the barrel roll. Starfox wants more barrel roll 😂😊