so the 185,50,16 = 23.2 inch dia
while std 165,60,14 = 21.7 dia
im running 185.60.14 continental eco tyres of which = 22.7 dia
so std are 1 1/2 of a inch smaller and 185/14 are 1/2 of an inch smaller so so you would get away with them
thats going of the working out the rough dia size of the tyres
would check tho how the wheels/tyres fit within the car such as to the arches and steering and offset cause ive gotten close to the arches when the car had a heavy load and was near the bump stops
also im assuming its a 1.0? or could be a 1.4 cause the increased tyre size will up the gearing alittle and on the 1.0 may seemed little over geared
also for the speedo it will be about correct or adleast my is with the 185.60,14s on its within 3mph out even over 70mph along with much improved handling specially in the corners
just to say aswell im running a 1.3 and you can tell abit of gearing difference but minor