Bitcoin already forked once.
Remember what happened to the price?
if you're talking about the 2013 fork, nothign really happened, there was a minor dump after the 230 peak, but it started before the fork so it's not sure if it was cause by the fork or what
Yep, lasted about half a day then rose quickly after that.
And that was an unexpected fork. Imagine how easy the transition will be when we can pretty much watch it happen down to the hour.