Generic CS20-Class QS Dirt Bike (72V 5000W 40.6Ah)

A 72V off-road electric dirt bike on the shared Chinese "CS20-class" commodity chassis, sold via the AliExpress Eshiner Store. This 72V 5000W 40.6Ah configuration uses a genuine QS Motor rear hub (QS205 V2 on the 3–5kW tiers, QS273 V3 on the 8kW+ tiers) with a Sabvoton or normal-wave controller and an SW900 display. High-carbon steel frame, 21-inch front / 19-inch rear motorcycle wheels, Zoom 680DH USD front fork, air rear shock, and 4-piston hydraulic disc brakes. Power labels are QS nameplate/peak figures — real continuous output is gated by the controller and is substantially lower.