While cruising Facebook Marketplace, I came across this gem. You have to give them credit for covering a good amount of bike styles all in one. You've got your sport bike, cruiser, and off-road all in one.

 

Hey, I'm not seeing any image here as to the Frankenbike but you say it being off Farcebook Markretplace I'm reckoning it's this one, I "think" looking at the motor it may have started life as a Suzuki GSX600F the fully faired model. Neer was overkeen on those bikes they seem to always suffer from engine problems a lot of people won't touch them, including me, I remember it starting off at £150 its now gone down to £65