Shimano PD-ED500 User Manual page 13

Adjusting the cleat holding force of the pedals
In order to prevent accidental cleat release and ensure that release is possible when needed, make sure
that the cleat holding force is properly adjusted.
If the cleats are not adjusted equally, it can cause the rider difficulty in engaging or releasing the cleats.
The cleat holding force for the right and left pedals should be adjusted so they are equal.
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