It's not just a specific model line, ALL Harley's "resale value" has dropped. Why? Because there is no more "Demand" for the bikes as there is plenty of "Supply" to be had. Harley's were only an investment(a toy is NEVER an investment anyway ) when they had 1 assembly plant and you had to plop down money on a new bike to be put on a wait list and you would get your new Harley in 2 years. This is when HD bike prices, both new and used especially, were at their highest point. Now that you can walk into a Harley dealer and ride out on a new bike of your choice, there is no demand for the used bikes now. So, the used bike prices will continue to drop to a more reasonable range
If HD wants to get resales up they need to short the market new bikes and jack up MSRP. If new bikes were selling for $3K over MSRP, those used bikes would be sold fast. They are going to cut production more soon. They are still closing facilities and they are downsizing the york plant.