yes 14 inch wheels are legal on a 120y.maximum width allowable by rta rules is 6 inches.this is decided by car weight,& the maximum width for both 1200's & 120y's is 6 inches.however,any insurance company will tell you 5 inches.this is because their policy is 1 inch over standard width & 1200's & 120y's came out with 12 x 4's.of course that is only main stream insurance companies,like the nrma,so shopping around should get you coverage for wheels.i'm not too sure if you can get wider wheels engineered.120y's have large wheel wells & i've seen 14x6.5's that looked lost in there.hope the info is of use.