I have read that some motors will make a ticking or tapping noise if the fuel pump is not completely full (system sucking air into pump), but I have no idea if that is true on your motor
If the noise was a rod or main bearing it would be a rather dull metallic rap and not a ticking noise deep in the engine (the front end of the engine). That would very likely be followed by a low oil pressure alarm which you apparently are not experiencing. A ticking noise may indicate it's time for valve adjustment and would be heard in the cam cover area of the engine (the rear end of the engine). Where that noise is coming from would help has determine what the issue is (if there is one).
