YEENON LR-AI Leica R to Nikon Ai Adapter - for DIY lens mount conversion.

Front Mount: Leica R mount lens

Rear Mount: Nikon AI mount camera body

Weight: 33g

The LR-AI Leica R mount to Nikon AI mount basic adapter is suitable for all Leica R lenses (including ROM version lenses).

The LR-AI adapter retains the previous YEENON precision while improving upon the shortcomings of similar adapters in the market. Its main feature is the ability to set effective aperture travel limits. This YEENON adapter has also been modified to be compatible with almost all R lenses.

Installation method of LR-AI adapter on the Lens is exactly the same as LR-PK. Below is an example using LR-PK adapter to illustrate the installation steps:

(I) Disassembling the Original Leica R Lens Mount

1. Set the lens aperture ring to wide open and rotate the lens focus ring to the closest focusing distance.

2. After removing the six screws on the bayonet of the lens and the three slotted flat head screws on the dust plate. 

3. Hold the lens vertically downward, gently lift the lens bayonet and dust plate, paying attention to whether the steel ball used for aperture positioning is left on the lens body or in the bayonet positioning hole. Remove the positioning steel ball first and set it aside.

4. Disassemble the 2-cam or-3 cam (for 1-cam: If the disassembly and screw positions are the same as shown in the diagram, it is suitable for this adapter. If it is a non-disassemblable 1-cam, it is not suitable for use with this adapter).

5. Keep the removed parts properly for future reinstallation when needed for the R-mount lens.

(II) Installation of this YEENON Adapter

1. Place the aperture positioning steel ball on the hole with a spring, and if possible, apply some grease (lubricant) on the hole. Align the holes for the steel balls inside the Yeenon adapter with the steel balls, and roughly align the six screw holes with the six holes on the ring. 

2. Then, place it vertically. Rotate the adapter to align the six holes with the six screw holes. Remember to keep the lens vertically placed, the aperture wide open, and the focus set to the closest distance.

3. Press down on the adapter with your hand, rotate the aperture ring to check if the aperture positioning steel ball is installed correctly. After feeling it is in place, install three screws first, and check again if the aperture ring works properly, then install the remaining screws and tighten them.

4. Setting the aperture ring travel limit

Rotate the aperture ring to wide open (e.g. f/2.8). Slightly loosen the illustrated screws (A & B), pull the limit piece (C) out to the lever side, and then tighten the screws.

Rotate the aperture ring to the minimum (e.g. f/22), slightly loosen the illustrated screws (A & B), pull the limit piece (C) out to the lever side, and then tighten the screws.

The Yeenon adapter installation is done..