How? The OP clearly stated he used grease on installation, albeit copper grease, which may not be ideal but should be fine. It shouldn't cause the crank to snap, basically.
Because correct installation of Campag pista cranks to campag ISO BB is dry.
Anything else is incorrect installation.
@gizmond started
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Because correct installation of Campag pista cranks to campag ISO BB is dry.
Anything else is incorrect installation.