Does the Catholic Church officially claim that the Bible is insufficient without tradition? I read this quote at the Christian Research Institute's site:


  One, the fact that Scripture, without tradition, is said to be “God-breathed” (theopnuestos) and thus by it believers are “competent, equipped for every good work” (2 Tim. 3:16-17, emphasis added) supports the doctrine of sola Scriptura. This flies in the face of the Catholic claim that the Bible is formally insufficient without the
  aid of tradition.


Does the Catholic Church officially claim anywhere that the Bible is insufficient without tradition?
Yes she (Catholic Church) does.  I've copied the pertinent parts from the previous poster's quotes to show this.


  82 As a result the Church, to whom the transmission and interpretation of Revelation is entrusted, "does not derive her certainty about all revealed truths from the holy Scriptures alone. Both Scripture and Tradition must be accepted and honoured with equal sentiments of devotion and reverence."


While it may or may not be true that her Tradition sources to apostles, since after all, the Orthodox say the same thing, yet the two groups contradict at a number of well known Tradition points, the whole point in answering your question is for them, Scripture alone as regards all things necessary for salvation, is incomplete.  They are quite clear and open about this.  Why someone would think otherwise is beyond the scope.

PS From the authentic Catholic mouth 1965:


  Consequently it is not from Sacred Scripture alone that the Church draws her certainty about everything which has been revealed.


DOGMATIC CONSTITUTION ON DIVINE REVELATION DEI VERBUM

Can't be any clearer than that.