What model year? If an early model, pre '07, take the comp nut to a machine shop and have .030"-.040" shaved off the end of the nut. Common problem with early models and factory tolerances. Although the specified torque may be applied, sufficient clamping pressure may not be applied and so the comp nut can work itself loose over time. HD used to sell spacers to remedy this problem but I doubt if any are still available since the new style comp was introduced. Check out the attachment for a better explanation.