Here are some videos of Russell Sutton nine cylinder radial engine he built and is working on a 14 cylinder radial engine using Yamaha XV1700 warrior top ends.

https://www.youtube.com/watch?v=p-qtqykVEew

https://www.youtube.com/watch?v=q3NgpLnai7k

https://www.youtube.com/watch?v=vAhAPF2B8Ao

https://www.youtube.com/watch?v=un9BY0F9x-o

https://www.youtube.com/watch?v=7WAtEvkAQs4&t=3s

https://www.youtube.com/watch?v=0AHjWHFWALU

https://www.youtube.com/watch?v=syVHgmoQ6FU&t=117s