  In a group, a non-trivial element is called a generalized torsion element if
some non-empty finite product of its conjugates equals to the identity. We say
that a knot has generalized torsion if its knot group admits such an element.
For a (2, 2q+1)-torus knot K, we demonstrate that there are infinitely many
unknots c such that p-twisting K about c yields a twist family, which consists
of hyperbolic knots with generalized torsion whenever |p| > 3. This gives a new
infinite class of hyperbolic knots having generalized torsion. In particular,
each class contains knots with arbitrarily high genus. We also show that some
twisted torus knots, including the (-2, 3, 7)-pretzel knot, have generalized
torsion. Since generalized torsion is an obstruction for having bi-order, these
knots have non-bi-orderable knot groups.
