As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE LT MLG WOULD NOT RETRACT AFTER TAKEOFF FROM NRT. A VISUAL CHECK CONFIRMED THE GEAR WAS DOWN. THE AIRCRAFT WAS RETURNED TO NRT WHERE IT LANDED WITHOUT INCIDENT. THE LT MLG RETRACT CYLINDER WAS REMOVED AND REPLACED, BUT THE PROBLEM REMAINED. MAINTENANCE FOUND THE LT MLG DOWNLOCK CYLINDER RESTRICTOR AT FAULT. THE DOWNLOCK CYLINDER RESTRICTOR WAS REPLACED. THE LT MLG WAS SWUNG IAW MM 32-30-00, PAGE 501 AND OPERATION CHECKED GOOD.