Joined: Nov 2005
Posts: 5,768
Likes: 10
Bikes: Cinelli, Paramount, Raleigh, Carlton, Zeus, Gemniani, Frejus, Legnano, Pinarello, Falcon
Cottered crank?
The flats on the spindle are wider than the cotter bolt, allowing some adjustment in and out to the arm on the spindle. You'll need to remove the bolts, re-adjust and re-seat.
Or are the bb cups or the chainring loose?