I just purchased a used Scag V-ride 52" stand-on mower. Something that feels a bit scary to me is that when I stop on a hill, the machine will continue (slowly) to roll unless I actuall "bump" the drive to the reverse. If I shut the machine off on level concrete I can also push the machine by hand, wheels rolling. Theres resistance, not "free wheeling" but it still rolls. I've checked the dump (bypass ) valves on the pumps and they are tight. Do other mowers behave this way? Thanks