Standard fitment for the Junior was a 520-12 crossply, which can be replaced with a 135R12 radial tyre if required.
The F11 had a 520-13 crossply in 1963. and a 550-13 from 1964, and the F12 a 550-13 from release. These can be replaced with a 145R13 radial if required.
The Junior was a small saloon and cabriolet, powered by a small, three-cylinder two-stroke engine. A popular car, as it was cheap and roomy, it was upgraded to F11 and F12 specification in 1963.