Position Sizing

Entered the stock after a clean Cup n Handle breakout. First entry was at 560 with a 9%sl, second at 595. Average buy was 578 for two positions. My sl for both the positions was 535.
But the same stock reached 640plus which is more than 12% from my first buy, i moved my stops to break even @580. Traded this stock for an average returns of 33% on both the positions. It added close to 7% returns on my pf. Closed 90% of the position and holding a small position for study purpose.