  Let G be a connected, complex reductive Lie group with maximal compact
subgroup K, and let X denote the moduli space of G- or K-valued representations
of a rank r free group. In this article, we develop methods for studying the
low-dimensional homotopy groups of these spaces and of their subspaces Y of
irreducible representations.
  Our main result is that when G = GL(n,C) or SL(n,C), the second homotopy
group of X is trivial. The proof depends on a new general position-type result
in a singular setting. This result is proven in the Appendix and may be of
independent interest.
  We also obtain new information regarding the homotopy groups of the subspaces
Y. Recent work of Biswas and Lawton determined the fundamental group of X for
general G, and we describe the fundamental group of Y. Specializing to the case
G = GL(n,C), we explicitly compute the homotopy groups of the smooth locus of X
in a large range of dimensions, finding that they exhibit Bott Periodicity.
  As a further application of our methods (and in particular our general
position result) we obtain new results regarding centralizers of subgroups of G
and K, motivated by a question of Sikora.
  Additionally, we use work of Richardson to solve a conjecture of
Florentino-Lawton about the singular locus of X, and we give a topological
proof that for G= GL(n,C) or SL(n,C), the space X is not a rational Poincar\'e
Duality Space for r>3 and n=2.
