There's never really a right or a wrong time to sell. It really just comes down to investing/ trading styles, which is determined mostly by goals and temperament.

I'm an active trader, so I try to profit from price swings, but I'm also an investor who pours profits into markets that I believe will grow over time. With bitcoin, I both trade and invest.

Even if I'm almost certain that the price will take a dive, I still won't sell more than 1/3rd of my position and I've made a pledge to myself to never touch at least 10 of my bitcoins for at least another five years.