NHTSA Complaint #10280347 — 2008 ZAP XEBRA

THERE IS WHAT I BELIEVE TO BE A DESIGN FLAW IN THE NEWER SUNL VIP MOTOR SCOOTERS. THE ORIENTATION OF THE THROTTLE CAM RETRACTION SPRING END, THE LENGTH OF THE THROTTLE CAM RETRACTION SPRING END AND THE LONG DISTANCE FROM THE THROTTLE CABLE MOUNT TO THE THROTTLE CAM (ALLOWING SLACK IN THE METAL BRAIDED THROTTLE CABLE) ALL CONTRIBUTE TO ALLOW THE END OF THE CAM RETRACTION SPRING TO SNARE THE THROTTLE CABLE, HOLDING THE THROTTLE OPEN DURING OPERATION. THESE SCOOTERS DO NOT HAVE A WAY OF DISENGAGING THE DRIVE DUE TO THE USE OF A CENTRIFUGAL CLUTCH IN THE DRIVE SYSTEM. THEREFORE WHEN THIS THROTTLE IS HELD OPEN, THE SCOOTER CONTINUES TO ACCELERATE. IN THIS CRASH, THE THROTTLE STUCK WHILE THE SCOOTER WAS HALFWAY THROUGH A TURN AND THEN "RAN AWAY". THERE WAS TOO LITTLE TIME TO REACT. I DISCOVERED THE PROBLEM IN THE CRASHED UNIT AND CHECKED SEVERAL EXEMPLARS TO SEE IF THE PROBLEM THAT OCCURRED IN THIS CRASH WAS REPEATABLE, AND IT IS. I NOTICED THAT SOME OTHER SCOOTER TYPES HAD SIMILAR SUB-ASSEMBLY CONFIGURATIONS, HOWEVER, THE COMBINATION OF DESIGN ISSUES IN THIS UNIT HAVE MADE IT UNIQUELY DANGEROUS. OTHER UNITS CURVE THE RETRACTION SPRING END, HAVE SHORT RETRACTION SPRING ENDS AND/OR SHORTER THROTTLE CABLE MOUNT LOCATIONS FROM THE THROTTLE CAM ALLOWING LESS SLACK IN THE LINE. *TR