Hello Mso872 welcome to the forums. what do you mean it does not fit? your old BB spindle is square yes? does it just not go on far enough?
the problem is you bike has a double crank, from 20 some years ago, and it needs a longer spindle than your new crank requires. check with the seller or on the shimano website to see what spindle length you need.
odds are you current spindle is about 115-118mm and you ned a 103 or so.
OH what brand are your old cranks? shimano, SR, Ofmega?
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
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