[Jim Bob]

I bought a wee rooster in July because I wanted to hear the sound of it in the yard   
However 6 months later it hasn’t started yet. What’s going on ? It's now a big bird and looks the part but not a sound.

[chrismahon]

Two possibilities Jim Bob. First you may have a silent one, or very quiet anyway- quality much sought after in suburbia. Secondly he may have been introduced to an older established flock and has assumed a subservient position in the flock domination. As such he won't crow, because he's not allowed to show any sign of domination and would receive a sharp reminder if he did. You could try putting him on his own for a while and see what happens? We've had hens crow when removed from the rest of the flock- they become master of their flock, even though they are the only bird in it.

[Backinwellies]

We've had hens crow .

WOW ..... that is amazing!

[Richmond]

He may just be quiet as Chris says. With no nearby competition he might not feel the need to assert himself.
Presume he is healthy and active in every other respect? Eating and drinking normally? Is he treading the hens at all? Appreciate they may not be in lay atm so he might not be interested but some cockerels will attempt to tread regardless.