History
Most US 50V Mobylettes use the AV7 two-stroke with a variator (continuously variable transmission) — not a scooter, but not a single-speed Puch either. The base 50 model used a single-speed dimoby transmission; the 50V added the belt variator that defines most US tuning culture. Stock exhaust and variator weights often cap RPM before jetting enters the conversation.
Quintessentially French: charming, quirky, and a cult parts scene. Motobécane built millions of Mobylettes for domestic commuters; US imports skew toward late 1970s and early 1980s step-through frames with painted steel tanks. Petcock leaks and tank rust are common on barn finds.
Moby people are loyal for a reason. The bikes are light, start easily when the carb and coil are fresh, and look like nothing else on the road. Restoration threads obsess over correct decals, Gurtner rebuilds, and finding a tank that is not pinholed.
First mods most owners consider: a performance exhaust and a clean fuel system. Do both before you chase jetting — a restricted exhaust will fool you into thinking the carb is the problem.
Quick specs
| Engine | AV7 (piston-port) |
| Transmission | 50V = variator · 50 = dimoby single-speed |
| Carb | Gurtner (Encarwi on some) |
| Notable issues | Tank rust, petcock leaks |
Three build paths (mild → wild) → Jetting guide Manuals & PDFs →