When I was a young teenager, 14 or so, my grandfather became sick with Alzheimers. My family moved in with him to spend some time with him, help him live independently for awhile longer, help get his affairs in order, set up nursing home, etc.
Anyhow, he lived in a big house on a hill in oregon. He was a retired jewelry store owner/property developer and spent his retired life going to estate sales and filling his 2 separate shop buildings and garage with his "deals" of which included 20 or so 3 wheelers.
My younger brother and I would head down to the shop and work on them and get them running and act like idiots on them. My younger brother chose to ride a very early honda 3wheeler, a us90, that sat really low, had wide axles and tire (He was smarter than me..) There was a 200cc Honda that had hi/lo range which of course was the one I had to ride. It took me awhile to realize it had that and one day I switched it into hi range, I was flying up and down the street and it scared my extended family (Not my parents for some reason) One day the tire was low and it rolled over and threw me off, I learned my lesson about being lazy and not airing up tires then. .
Anyhow the neighbor kids were a bit older and they would hang out and one day I rode doubles on the 200 with the older more troublesome teen through these really scenic countryside hills... it turns out it was a farmer's field and we were damaging it by riding over the freshly planted crops. The farmer confronted my mother about it and she gave him my beloved 200cc hi/low range honda 3 wheeler.
After than I rode the second largest one in the fleet a 185. I couldn't get the 185 running right and in hindsight I think it was due to it needing valve adjustment. It was given to me and I later sold it for way too cheap when moving. . the rest of the bikes were sold much earlier for next to nothing at the estate sale / auction when my grandfather died.
Also there were some larger Kawasaki ones in another shop building but it was down a steep gravel hill and we never thought to steal/borrow the jeep and pull them up into the larger more equipped shop and get them running, good thing I guess, lol.
Anyhow that was my introduction/crash course to 3 wheelers, and the best summer of my life so far.
Oh ya, also at least twice we managed to install the slide incorrectly in the carb and start the engine in gear. They would take off like rockets and scare the hell out of us while destroying and running over everything that got in its way, hit and miss engines and almost a Peugeot car.