"...a 400cc diesel engine, basically a lawnmower, but it can haul nearly as much as a Ford Ranger..."
My father had a "lawn & garden tractor" which is a step above a lawnmower, as it can pull a trailer loaded with wood & other such things. So, I had to look it up to compare the "cc" rating of the engine to wrap my head around the numbers. The lawn & garden tractor he had is no longer in production, but best I can tell from websites that have specs on it say it had a "18HP Briggs & Stratton 693cc 2-cyl gasoline engine," so that gives me a little more insight into your tuk-tuk. It's still quite the little "hoss" despite its size! So glad you have something like that, and the MPG is killer! 🙂
If I put that engine in our tuk-tuk it would feel like we had turbo boosters. could probably break the 50 mph barrier 😉.