I find nothing wrong with letting a bike or bike parts "bake" on Ebay or CL for multiple cycles, especially if it's not costing me anything to relist. Sometimes it takes time for the right buyer to notice your item(s). If you price it to move in one cycle, that's fine, but you might be leaving money on the table (if that matters to you). Many of the things we sell in these venues aren't commodities, and don't appeal to a broad swath of the population.