Junak is a brand Polish motorcycles, the only four-stroke models produced in Poland between World War II and Revolutions of 1989. The name literally means "brave young man". Produced by Szczecińska Fabryka Motocykli (Szczecin Factory Motorcycles) in three variants: M07, M10 and B20.

　　During the nine years of production, 1956-1965, a total of 91,400 Junak motorcycles were produced. Several models were produced, namely: 10,000 tourist M07, rally M07-R and cross M07-C models, 2500 three-wheeled B20’s, 8500 sidecars type WB1 and W03 while the rest were M10 models. The Junak frame was produced by SFM in Szczecin. During the transition from model M07 to M10 from 1960 to 1961 about 20,000 M10 models possessed some characteristics of the M07 model such as the headlight housing.

　　The Junak was designed in 1951-1952 in Automotive Industry Design Bureau under the leadership of J. Ignatowicz. At that time Junak was superior to many well known motorcycles. This was not surprising since experienced engineers designed the Junak basing their knowledge on T. Rudawski’s group. T. Rudawski was the father of pre WWII Sokół motorcycles, which is also the reason why the Junak engine has many characteristics of the Sokół 600 and 500. The governing system and inconvenient localization of the production line led to difficulties in ensuring quality. The same reasons hindered the production of the newer engines S130, S131, and S132.