Bike Forums - I.D. 1993-5 Record or Chorus

1995 was the year they started marking it on the components. So if it doesn't have the name of the group on it it's older than 1995. In any case, record cranks always had the hidden bolt, so that is an easy one.
The other components are more difficult. The rear derailleur is more difficult. The most easily identifiable difference in 1993/4 is that record has a hex nut (likely 8m) for fixing the shift cable (I believe it could take a 5mm allen key as well, while chorus (and others) had an allen nut only. The front derailleur for record was nearly identical to the original C-record introduced to the public in 1984 (tested by pros in 1983 I am sure). I can't tell the difference between the ergo power levers. The hubs, record had alloy dustcaps and different skewers, chorus had steel dustcaps. The seatposts were still aero in 1994 and chorus had the hidden allen heat while record had the exposed. 1994 saw the last of the C-record era designs introded in the early 1980s which lasted about a decade. The record cranks are essentially the same as the original C-record. 1995 saw a revamping of the line-up with group designations right on the components, finally making it easy for us to differentiate. Hope this helps. If you post pics we can help you ID stuff.