What was found
(CAN) AFTER TAKEOFF, SHOCK ABSORBER MESSAGE ON ECAM, RECYCLED GEAR, GEAR WOULD NOT RETRACT. RETURNED TO BS, ARFF NOT CALLED OUT, NO EMERGENCY DECLARED. LANDED WITHOUT INCIDENT. LANDED OVER WEIGHT. DUTY PILOT ADVISED. FOUND SHRADER VALVE LEAKING, R & R SHRADER VALVE, SERVICED WITH NITROGEN TO CORRECT OLEO DIMENSIONS PERFORMED NOSE GEAR RETRACTION TEST, 2X NO FAULTS IAW AMM TASK 32-30-00-201.