Also might be an idea to 'centre the tube'. Looks a tad too far forward.
Ideally should balance in both axes with 'no locks on'. 33South has the solution.

L.
ps. Adjust for as near to zero play in the drives/cables.
pps. Any sports store will/should have weight lifting equipment. Just take your counterweight with you for hole size. Not sure of cost, maybe $10/$20??? Could use lead weight off a divers belt.