Help with no spark
#1

Im working on a 12.5hp 2cyl briggs and stratton and it wouldnt start so I checked for spark and it has spark if you pull a spark plug out and the engin turns over really fast. With the spark plugs in it turns over fast enough to have spark but it doesnt. It only has spark if its spinng really fast. Is there something I can to to get better spark? I already took sandpaper to the magnent on the flywheel.