If you have two right-handed cranks & pedals, that is a problem. Both cranks
should be the same where they attach to the hub. The pedal thread must be
opposite. So both the crank & the pedal must be left-handed (tightens
counterclockwise) for the left side of the unicycle.
As the wheel goes around, the crank does a full rotation around itself every
time the wheel does a revolution. But the pedal always faces up. So while the
righthanded pedal will tighten more, a right-handed pedal on the left side
will loosen.
But if your problem is with the crank going loose, not the pedal, it could
be that the extra movement on the loose pedal loosens the crank, or it could
be an unrelated problem. So, read all the other posts that you received in
this subject.
Alberto Ruiz Ruizb@aol.com