RE: 4 stroke spool down???
Are you on pavement or grass?
If pavement, well, the best solution is toangle the main gear in toward each other.. offering some resistance to the forward movement.Another solution, if on pavement, is to put some tubing between the wheel hubs and the wheel to offer some braking resistance to the wheel.
If you are flying on grass.. well, are you sure of your RPM? Mine idle at or around 2500 RPM and don't move at all until I throttle up.
CGr.