A Brief History of the Marque
Pietro Vassena, already known for designing a variety of engines for other manufacturers, built a motorcycle with a horizontal 125cc two-stroke engine and two-speed gearbox, introduced in 1926.
Having established workshops in Lecco to produce his machines, the Vassena 125cc saw only detail improvements before production ceased with the onset of the financial crisis.
After WWII Vassena designed engines for Rumi. Other manufacturers which benefitted from his considerable skills included Pirola and Amisa, and in 1953 he formed the Industria Motori Vassena company which built motorcycles marketed as both IMV and KZ (listed in some sources as K2).
Sources: MC Storico Conti, Tragatsch p289, Moto di Lombardia