  Cold reaction valleys in the radioactive decay of superheavy nuclei
{286}^112, {292}^114 and {296}^116 are studied taking Coulomb and Proximity
Potential as the interacting barrier. It is found that in addition to alpha
particle, 8^Be, 14^C, 28^Mg, 34^Si, 50^Ca, etc. are optimal cases of cluster
radioactivity since they lie in the cold valleys. Two other regions of deep
minima centered on 208^Pb and 132^Sn are also found. Within our Coulomb and
Proximity Potential Model half-life times and other characteristics such as
barrier penetrability, decay constant for clusters ranging from alpha particle
to 68^Ni are calculated. The computed alpha half-lives match with the values
calculated using Viola--Seaborg--Sobiczewski systematics. The clusters 8^Be and
14^C are found to be most probable for emission with T_1/2 < 1030s. The
alpha-decay chains of the three superheavy nuclei are also studied. The
computed alpha decay half-lives are compared with the values predicted by
Generalized Liquid Drop Model and they are found to match reasonably well.
