The monoshock spring is pushing up on a "V" and we cannot see if it is a triangle or not.
But it would need something (tube) coming from the bottom of the frame to keep that "V"
from being pushed upward. Also the "V" or upside down triangle would want to tilt backward of forward and what will prevent that. The frame tubes are only 1/16 thick.
Anyway the two kinds wheels on the bike bother me,mixing spokes
and cast wheels just makes it even more pronounced that
it is a mis match of parts, years, and styles.
That 1950's-60's rear taillight pointing slightly down
looks like it is laying an egg or taking a poop.
Old tail light modern rear suspension ,one wire wheel ,one cast wheel, walnut dash, etc.,.
Old.....New...Old...New ...Old....new. Mixed up concept.
No rear support on the exhaust so the whole exhaust will bounce up and
down until the cylinder head studs and gaskets are beat up.
Then the nuts will not come off of the beat up threads.
On a Roadstar Adventure.