I wanted to know if it’s possible to put a 85/86 engine on my 84 model. Is there anyone who knows about that?
Thanks!
i recently bought a vf1000fe (1984) that had the ff (1986) engine fitted, it looked i tight squeeze to get the engine in and im not too sure wether everything lined up correctly as the previouse owner had made his own engine spacers, also it was impossible to remove the rear rocker cover whilst the engine was in the frame…
Thank you for the answer! 
If the new engine is with line bored cams, frame changes may be needed. The cylinder heads are wider in newer models.