I have a couple motors that are almost the same model, JDH-2250-CQ-IC and the only thing that the label says is that they're 24 Volt DC.
I couldn't find any more info on the internet either.
I also have "saved" some hitachi servo motors from the same kind of equipment.
They are the same size and have the same part number on the label.
I have specs for this motor (from the label) :
30 oz/in cont.
Since they have the same partnumber and were used in the same application I asume they're interchangable and their specs are very close.
I hope it helps.