Originally Posted by
slow_jun
should be filed down and leave no trace of excess material, else that will cause some leaking issues on your shocks.
Keep in mind that these are mass produced injection molded parts. The area that you are looking at is the gate that fills the cavity with plastic, they usually place the gate on the top or bottom of the piston so the complete diameter is round and you do not need to file anything. I don't recall if Tekno did this to their pistons.