When you strike the rod with another metal object, like a wrench, it should sound like a tuning fork and ring, if it is a dead sound, like just a thud, it is cast, but all of those rods are forged according to Honda, but one thing to keep in mind is that Honda forges the rods to reduce weight, NOT for stregnth, they are stronger than cast rods, but not nearly as styrong as AM forged rods. Also Hoda uses two dofferent types of forgings, thaere are cast forgings like the RJA and RDJ, then there are powder forgings, where the metal comes in as a powder then is heated and beaten into shape like the RGL, both forging methods are equally as strong in design.

 

When you strike the rod with another metal object, like a wrench, it should sound like a tuning fork and ring, if it is a dead sound,

NVA-Av6 you are right.. i just did a test and it does sound different..
the first rod is from our J30A4 the second is the RGL rod


the following video is taken with SonyErisson K810i
somehow the sound recording is lagging

http://img531.imageshack.us/my.php?image=mov00058fk6.flv

 

Dead on answer.