Is the radial fan a Conti?
I've seen a few different motocycles with radial engines, both inline and transverse, modern and old.
My favourite is the Killinger & Freund FWD circa WWII...
... which is quite similar to the Megola, another radial in the front wheel type bike from the 30s.
Here's an old Plymouth you might like, CDB:
It's also featured on Jay Leno's Garudge.
I've always thought a large RC radial engine to power a Messerschmitt KR200 would be cool...
Or stuff the RC-radial into a Boardtracker frame (more my style than the modern chopper stylings with radials):
There's a guy who handmade a radial engine that spins, about the size of the one above, but can't find the link again though.
Another guy took a single cylinder from an aeroplane radial to power a bike, the NSU BISON 2000 — a 2L thumper!
Some random radial...
150bhp, nine-cylinder Rotec Radial R3600
Rotec 2800 is a 7 cylinder, lop out 3 cylinders and you’ve got a 1200cc W engine, NOICE! In fact, the spacing between the cylinders could be further reduced.
Use an Egli Vincent frame (mono-shocker even better), hang the engine off of it…
VW-based W or V ::
inline or transverse ala Motoguzzi
18-cylinder 700cc !!
https://www.heilemann-sternmotoren.de/en/ THIS WOULD LOOK GREAT IN A 192x LOOP-FRAMED BOARDTRACKER but it’s an RC meth-head, could it run on gas?
Evolution Seven Cylinder Radial model airplane engine 35cc, 77cc, 260cc
WWI Gnome engine…
VALACK VM RF - 800cc 7 CYLINDER RADIAL
Sorry about the lack of original photos, all these were swiped from the Etherwebs.