The HPV-1000 is a police motorcycle ridden by San Andreas Police Departmentpolice bikers.The bike also resembles a Wayfarer but modified. It is very fast and agile (below higher end models such as the FCR-900 and NRG-500), although the player can fall off easily if they have minimal "bike skill". If the Rhino or Hunter is not yet available, this bike is a good choice for completing the Vigilante side mission - mainly because the player can fire a submachine gun straight ahead or on both sides, allowing them to take out the opponent easily. Although its siren is no longer effective in prompting oncoming vehicles to move out of the way, its compact motorcycle design allows it to navigate around traffic far better than full-sized cars.
The HPV-1000 assumes a unique model that isn't shared by another motorcycle, and bears resemblance to a police Kawasaki KZ1000. HPV is probably a reference to human papillomavirus, which is one of the most common STDs.
In a beta version of the game, there was "911" written on the rear, and "SAPD" was replaced with "POLICE". In another beta version, there was a LSPD HPV-1000, implying that there would be a city-specific version of each HPV-1000, rather than a state-wide version.
HPV most likely stands for 'Highway Patrol Vehicle'
HPV is also an abbreviation for the Human Papiloma Virus.