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...I just this minute installed an Octalink BB unit in a frame I'm rehabilitating.
It reminded me that you want to have your special Shimano BB installation and removal tool firmly bolted in there before you apply any impact wrenching (or much of anything else in the way of torque).
Otherwise those little teeth, either on the BB unit, or on your tool, are just going to disengage and round off. Once that happens, you lose a lot of possibilities.
I was a little tired, and should have stopped on this project a couple of hours ago, so on my first attempt, I tried to install it backwards.
