two-smoker said:Bryantr, that is in no way an FZR frame. FZRs- both 600 and 400- have beam-type frames, the difference is steel versus aluminum, but you'd have to be an expert to see the differee at a glance. That loks like the original frame with FZR suspension and wheels. And the 660 you refer to is an Early YZF600 motor with an FZR600 crank, not a YZF topend on an FZR.
I know what an FZR is. I'm sitting next to one. I was referring to someone suggesting to swap his engine to the FZR frame.
You can build a 660 the way you mentioned if you get a crank seal from some European engine that I cant remember the name of, or FZR cases trans and crank with a 4mm base gasket YZF jugs pistons head carbs. Or so I've read.