A fully decked out motorcycle which has been enhanced through add-ons to make them appear more stylish and/or more comfortable for longer rides. Add-ons that result in a motorcycle being considered a dresser include windscreen, backrest, good-time radio, CB radio, and saddlebags. After putting these add-ons onto a motorcycle that bike is said to be 'fully dressed' (or a 'dresser').
Damn, all you see are fools riding sportsters or dressers these days. No real bikers left anymore.