I have changed the description with instructions:

Instruction:

- Align the top hole first to the stock head pin position.
- Let the extra length of the main shaft sticking out under the main gear or use dremel to cut off the extra length.
- Since the main gear is 137T, adjust the motor position toward the main gear about 1-2mm so that the motor pinion and main gear mesh with each other well.
- When installing the auto-rotation sleeve, make sure DO NOT PUSH them into the oneway bearing. It could damage the bearing. Twist it slightly and gently force it into the bearing. It will fit in perfectly.
- If you got problem with the main shaft that cannot go through the auto rotation sleeve, use sand paper 600 to sand off the burrs on the shaft if there is any.
- Apply loctite to the set screws on the auto-rotation sleeve.

ct420,

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