While I have prepared a breakdown of the three most likely meanings below, please 🛵 1. BMS Zip Scooter (50cc) The most common reference is to the BMS Zip 50
BMS (Berliner Meeresschutz-Outdoor) is a German brand known for "SoftSkin" outdoor and sailing gear. In this context, "BMS zip" refers to their specialized garment construction:
A protective fabric cover at the top of the zipper to prevent chin chafing.