We have a “Open” class here in Aus that is basically for doing crazy stuff with Karts.
I was at a event recently where a racer had Twin KA100’s.
It was awesome, sounded great and kept up very easily with both a KZ 2 and a Twin reed valve. I’ll see if I can get a picture next time I see it.
There is now talk here of boring a KA100 over size to make it a 125 air cooled engine, and running that as a twin.
If only none of this cost money…