That's a flat 6, not a v6.

The engine he chose isn't really made for revving or higher rpm's at all. The opposite of a bike engine mostly. He cruises it very slowly so I guess it's purely an art piece. It's unique, I'll give it that. I tried to hear it but they kept throwing heavy electric guitar music over it. From what I could hear, sounded like it was doing little more than idle.

But can it go round corners...

Yes, Continental engines Some of which were produced by Rolls Royce, are horizontally opposed, not V engines....
No One in avitation running a Continental engine tries to Brag about their Rolls Royce.... Continental or Lycoming; Experience, Preference and Luck will play a part in which engine is in your aircraft...

Quite why he didn't make it electric drive is a complete mystery!

" who Brazilians believe got an airplane aloft before America's Wright Brothers". The Wright Brothers flew a plane couple of feet above ground. Santos Dumont flew his around Eiffel tower.......

Why no pictures or video of it turning? Can it? What is its tightest radius? Kind of dangerous to everyone around if it cannot.

Er, how does it stop?
And as for drive, am I right in thinking that the drum-like mechanism attached to a chain serves for driving the back wheel by friction, like a bicycle dynamo in reverse? Does this also serve as a brake?

Looks to me like if you leaned back a little too much to get sucked into that tire spinning around right at your back

Certainly is an amazing piece of machinery, art even. Practical ? Not in the least. Can't go around corners, can't put all that low revving Continental grunt to the ground, and brakes ? Who needs 'em ? But looks awesome......