I AM TRYING TO HELP MY SON WITH HIS SIMPLICITY REGENT 17 HP 40" DECK. iT LEAVES A STRIPE DOWN THE MIDDLE WHEN CUTTING. THE BLADES ARE NEW IJUST PUT THEM ON THEY ARE THE EXACT ONES THAT WERE ON IT BUT THOUGHT I WOULD TRY. I MEASURED THE OVERLAP AS THEY ARE A TIMED BLADE AND THEY OVER LAP BY ABOUT 1". ANY IDEAS WOULD BE APPRECIATED.