Jaeger-LeCoultre Caliber 201 – Technical Overview from Document 1071_JLC

The Jaeger-LeCoultre Caliber 201 is a renowned manual-winding mechanical movement from the mid-20th century, celebrated for its reliability, precision, and traditional craftsmanship. Document 1071_JLC provides an extensive technical breakdown, including detailed component analysis, movement architecture, and servicing guidelines.

Technical Specifications

• Type: Manual-winding

• Functions: Hours, minutes, small seconds

• Jewels: Typically 17

• Frequency: 18,000 vibrations per hour (2.5 Hz)

• Power Reserve: Approximately 40 hours

• Diameter: Approximately 27.0 mm

• Height: Approximately 3.5 mm

This caliber is valued for its balanced design and was widely used in elegant dress watches requiring dependable timekeeping.

Movement Architecture and Features

According to document 1071_JLC, Caliber 201 includes:

• Small seconds subdial located at 6 o’clock, powered by the fourth wheel and pinion

• Two-bridge design providing structural stability and facilitating ease of maintenance

• Reliable gear train and barrel assembly ensuring consistent power delivery

• Shock protection system on the balance wheel to withstand impacts

• Smooth manual winding and setting mechanism, designed for comfort and durability

Servicing Notes

• Lubrication: Application of fine synthetic oils at escapement pivots, pallet jewels, and balance staff; light grease on barrel arbor and winding gears

• Regulation: Aim for amplitude of 250°–280° and beat error below 0.8 ms for precise timekeeping

• Small seconds function: Check for proper mesh and secure fitting of the fourth wheel pinion and seconds hand to prevent stuttering

• Keyless works: Regular inspection and maintenance of the setting lever spring and sliding pinion ensure smooth winding and setting

Applications

Caliber 201 was used predominantly in:

• Jaeger-LeCoultre dress watches of the mid-20th century

• Timepieces featuring classic small seconds displays and traditional styling

• Watches crafted in stainless steel or precious metals, commonly sized between 34 and 36 mm

Conclusion

The Jaeger-LeCoultre Caliber 201, as outlined in document 1071_JLC, represents a classic manual-winding movement that combines precision, reliability, and timeless design. Its well-balanced construction and ease of servicing continue to make it a favorite among collectors and watchmakers specializing in vintage Jaeger-LeCoultre wristwatches.