Utility motorcycles

motorcycles used by police

right|thumb|300px|Derny publicity material thumb|Derny Taon 125, 1955/1956 thumb|650cc Triumph TR65 Thunderbird "Stayer" first used at [[Leicester Velodrome in 1982 and now at Herne Hill Velodrome. Note the roller at the back and stood-up riding position that distinguish a Stayer from a true Derny.]]

motorcycle used by a fire brigade or fire department

type of emergency vehicle