Cog Size

kesher
kesher Posts: 44
edited November 2012 in Road buying advice
Does anyone know what is the smallest free wheel cog that can be fitted to the flip flop cassette of Mongoose Maurice 2012 bike?

It was supplied with a 18t/44 set up (freewheel and fixed cog). I'd like to fit a 13t cog; but I have been told that the diameter of 13t cog thread is too small and meant for a BMX and that the minimum size which will fit is 16t. Although someone else said that a 13t should fit.



THANKS