Will it do it? Probably, if you gear it right. I strongly suggest you not try it though, with no suspension. Chances are very great that it will bounce out of control at that speed.
Here you go. This bike
is a much better bet, and cheaper too.
I can get behind the idea of putting a V-twin in a large minibike frame for the fun of it. But if you really expect us to tell you it is ok to build such a machine and then take it out and do 80 mph on the highways, you are either insane or a jerk cop on a fishing expedition. You won't get anyone's blessing on here to do that.
In fact, I'm really beginning to suspect the latter is exactly what you are. It's just like on the gun forums when some newbie comes in and starts demanding information on how to convert something to full-auto, and trying to get someone to agree that it's a good thing to do: it's a dead giveaway that the newbie is a meathead JBT who thinks everyone is as stupid as he is.
So if that's you, go tell the chief it didn't work.