Product Description

SHIMANO 1002D IDLE GEAR L (RD20186)

Ensure Smooth Oscillation

The Shimano 1002D Idle Gear L is a genuine OEM replacement part essential for the precise operation of your Shimano spinning reel's oscillation system. Located within the gear box, this specific idle gear works in conjunction with the drive gear and worm shaft to ensure even line lay and smooth spool cycling.

If your reel feels "geary" or you are experiencing irregular spool movement during retrieval, a damaged or stripped idle gear is a common cause. Replacing this component with an authentic Shimano part ensures the tight tolerances and quiet operation expected from high-performance finesse reels.

Product Specifications

• Part Name: Idle Gear L (Large/Long)

• Manufacturer: Shimano

• Part Number (MPN): RD20186

• Schematic Code: 1002D

• Material: High-durability composite

• Installation Position: Internal oscillation system (often paired with Idle Gear B S)

Compatible Models

This part is specifically engineered for select high-gear (HG) and finesse models in the 1000-2000 size range. Please verify your specific generation and gear ratio, as standard gear ratio models often use a different part.

• Shimano Vanford F Series:

  • VF C2000HG F

  • VF C2000SHG F

• Shimano Stradic FL Series:

  • ST 1000HG FL

• Shimano Cardiff XR:

  • Cardiff XR C2000S HG

Note: This part is generally not compatible with standard gear ratio models (e.g., Stradic 1000FL or Vanford 1000F), which typically use a different idle gear.

Installation & Reference

To confirm fitment, cross-reference the schematic key 1002D or part number RD20186 with your reel's service diagram.

• Schematic Diagrams: For exploded views and part location verification, please visit www.reelschematic.com.

• Alternate Part Number: RD20186

Installation Tip: When replacing the Idle Gear L, it is often recommended to inspect the adjacent Idle Gear B (Small) and the worm shaft gear for wear, as these parts mesh together under load.