This project is a fully reverse-engineered replacement jockey wheel (roldana) for vintage Simplex / Peugeot 1980 bicycles, modeled from an original damaged pulley.
The original part is long discontinued, so this design offers a practical, durable alternative that preserves the bike’s functionality without altering its classic appearance.
🔧 Features
- Accurate 10-tooth profile modeled from a real Simplex pulley
- Correct stepped hub geometry for original metal bushing fit
- Outer wheel thickness only 2.40 mm, matching vintage design
- Central hub thickness 9.27 mm, like the factory part
- PETG-friendly design with minimal supports needed
- Optional PLA supports for clean separation (multi-material compatible)
⚙️ Recommended Print Settings
- Material: PETG (final part) / PLA support on touching parts
- Layer height: 0.20 mm
- Perimeters: 4
- Infill: 80–100%
- Supports: Touching build plate only under inner cone, support critical regions only
- Tree supports: enabled (Branch Ø 3 mm, angle 45°)
- Cooling: 0% first layer, 40–60% afterwards
- First layer speed: 20 mm/s
- Bed temperature: 80–85 °C (PETG)
🧪 Notes
- The central bore is dimensioned for the original Simplex metal bushing.
- Slight scaling (±1%) in XY may improve press-fit depending on your printer.
- This part was developed as a faithful functional replacement, not as a modern derailleur upgrade — it is meant to preserve the authenticity of a vintage bicycle.
🚲 Compatible With
- Simplex rear derailleurs (Peugeot 1970–1990 era)
- SX, SJ, and other plastic-body Simplex units
- Many other French vintage bikes using the same standard
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