Thanks to a comment by Jenn, we now know where the radial engine powered motorcycle #2 comes from, it's JRL Cycles in Black Hawk, South Dakota. The bike will be on display this year at the EAA flyin and air show in Oshkosh, Wisconsin and after that will be in Sturgis.
JRL is also an official distributor for the Rotec radial used in both motorcycles we wrote about.
There's not a lot of information on their website yet but that will probably change very soon.
Thanks for the tip, Jenn!
Link: JRL Cycles