Projects

Rebuilding a Solex 3800 engine

  • Mechanical
  • Engines
  • Restoration
The rebuilt Solex engine, glossy black, mounted over the front wheel of the moped
The engine after the rebuild, back on the moped.
Year
2023
Moped
VéloSoleX 3800
Engine
49 cc two-stroke

This VéloSoleX belonged to my great-grandfather. Its engine had not run for decades and was very dirty inside. In 2023 I took it apart and rebuilt it.

A Solex has its 49 cc two-stroke engine mounted over the front wheel, and it drives the tire directly through a roller.

The bare aluminium Solex engine casing, stamped Solex Moteur 49 cc, Made in France, on my lap before the rebuild
The engine before the rebuild. Serial number blurred.

What went into it

The parts list gives a good idea of the job:

  • Engine internals: crankshaft, stator and small-end bearings, piston rings, crankcase oil seals, a full engine gasket set and new clutch linings.
  • Fuel and ignition: the fuel pump diaphragm and its glass ball, fuel filters, an oil-bath condenser and a spark plug.
  • Intake and exhaust: a new intake and exhaust manifold and a new exhaust pipe.
  • The rest of the moped: tires, inner tubes, brake pads, the rear light, bulbs and a seat cover.
  • Cleaning: a thorough cleaning, and the chrome parts polished by hand.
Me sitting on the black VéloSoleX moped in a residential street
Back on the road.