For your consideration.
I believe that the Ariel Motorcycle has beaten him to the punch with the Ariel Square Four.
The idea belongs to Edward Turner from around 1928 who was later hired by Ariel to help design the engine. It went into production in 1930.
Below is the Ariel Square Four. Gurney just copied the idea and made a few improvements. It's not a new idea. That's common with many of today's "new" patents.
Eight gears, two chains & four sprockets.
I'm betting it will disappear just as fast as Smokey Yunic's two cycle that was very powerful for its size. And economical.