Traditional Kendama designs (like ours) allow for the Sarado (cups) to separate from the spike so that it can be re-strung. Over time, wood can expand and/or contract. If you restring your Kendama often, the repeated removal of the cups will inevitably loosen the fit. Oftentimes just firmly pressing the cups back down will fix the issue. If the cups become too loose, we have a trick for getting them to stay. Note: using super glue can permanently stick your cups to the spike, we advise against this.