What was found
AFTER TAKEOFF AND PASSING 10,000 FT, AIRSPEED ZIPPER DID NOT INCREASE TO EXPECTED CLIMB AIRSPEED, MAX AIRSPEED 268 KTS AT FL 360, ZIPPER RESTRICTED AIRSPEED TO 238 KIAS. DURING DESCENT, PASSING FL300 ZIPPER INCREASED TO 268. DURING APPROACH ZIPPER INDICATIONS WERE NORMAL WITH FLAP EXTENSIONS. FOUND VMO/MMO SWITCH ON THE P65 PNL TO BE IN THE ALTN POSITION. RETURNED TO NORMAL AND INSTALLED NEW SHEAR WIRE. PERFORMED OPS CHECK IAW MM 34-12-00-5. OPS GOOD.