My cassette is no longer locking with my free hub. It catches some
times and I can pedal for a minute or two but if I stop pedalling, go
too fast so I'm spinning, or change gear then the link fails again and
my cassette spins in the drive direction without engaging the wheel.

Any ideas where the problem is before I open it up so I know what to
look for? Is the hub? Is the cassette? Does it sound like I need a new
wheel?

--
rec.bicycles.off-road is moderated by volunteers. To find help solving
posting problems, or contact the moderators, please see http://rbor.org/
Please read the charter before posting: http://rbor.org/rbor_charter.txt