Determine the Manufacturing Date

The Earliest Paramount Serial Numbers

The very first Paramounts seemed to have had serial numbers starting with “A” followed by two or three digits. This seems to have been a system started by Emil Wastyn. We found a very early Paramount – claimed to be a 1938-9 vintage – with serial number A545.

Little is known about serial numbers for bikes built after World War II. Unfortunately, an office fire in 1948 destroyed the Paramount records. Numbers mostly followed a three-digit format – often but not necessarily with a “P” as the prefix.

By early 1959, serial number 949 had been reached, necessitating a new system.

The “New” System

This system was used from Spring of 1959 to the end of 1965. It was a sequence consisting of a letter followed by two digits, starting with A10, followed by A11 and so on until A99. When the B’s started out, they started with B10. Here’s a table of the codes and their manufacturing dates:

  • A10 – 4/1/59 (Approx).
  • B10 – 6/30/59 (Approx)
  • C10 – 10/30/59
  • D10 – 4/25/60
  • E10 – 8/1/60
  • F10 – 1/2/61
  • G10 – 5/3/61
  • H10 – 8/1/61
  • I10 – None
  • J10 – 2/1/62 (Approx)
  • K10 – 7/1/62 (Approx.)
  • L10 – 10/15/62
  • M10 – 3/1/63 (Est)
  • N10 – 7/26/63
  • O10 – None
  • P10 – 10/14/63
  • Q10 – None
  • R10 – 2/10/64
  • S10 – 5/5/64
  • T10 – 6/17/64
  • U10 – 8/19/64
  • V10 – 11/18/64
  • W10 – 3/11/65
  • X10 – 5/19/65
  • Y10 – 7/20/65
  • Z10 – 9/28/65
  • Z99 – 12/30/65

The First Serialized Date Code

This system was used from January 1966 through 1969. It consisted of three components –

  • Month Code: This one letter code corresponds to the month with A=January, B=Febuary and so on. Because I is not used, September=J and December=M.
  • Year Code: This one digit code is the last digit of the year – 6 is 1966.
  • Sequence Number: This two digit number represents the nth frame and/or fork scheduled during the month.

For example, H763 is the sixty-third frame or fork scheduled during August of 1967.

Capacity Added for the Boom Years

  • Month Code: This one letter code corresponds to the month with A=January, B=Febuary and so on. Because I is not used, September=J and December=M.
  • Year Code: This two digit code is the last two digits of the year – 86 is 1986.
  • Sequence Number: This two digit number represents the nth frame and/or fork scheduled during the month. During the peak of the bike boom, Schwinn would add another digit, sometimes producing as many as 500 frames a month.

    • For example, H7634 is the thirty-fourth frame or fork scheduled during August of 1976.

    Self-Describing Serial Numbers

    This system started in use during the mid- to 1994’s. It consisted of six components:

    • Size Code: The size code represented the center to top seatmast measurement, rounded to the nearest 5mm. For example, a 55cm frame had a serial number starting with 550. Mountain bikes required rounding since they were built in one or two inch size increments. Occasionally, custom frames might not have the same size as indicated by the serial number.
    • Product Code: This was not applied consistently. Up to some point in the early 90’s, it designated the fork length with forks short bikes getting an “A” progressing to large forks getting an “E”. Later, it was used to designate the kind of frame: A=Road, B=Off-Road, C=650C Road, E=Track.
    • Company Code: In the 80’s the code indicated the type of bike, where K=road bike. Later, especially after the formation of Waterford, this letter indicated the company. K was for Paramount and L was for Waterford.
    • Factory Code: A W followed to indicate a bike coming from the Waterford factory.
    • Month Code: This one letter code corresponds to the month with A=January, B=Febuary and so on. Because I is not used, September=J and December=M.
    • Year Code: This two digit code is the last two digits of the year – 96 is 1996.
    • Sequence Number: This three digit number represents the nth frame and/or fork scheduled during the month.

    Example: 540AKWE91042 was a 54cm road racing Paramount built at the Waterford factory. It was the 42nd frame built in May of 1991.

    Paramount Tandem Serial Numbers

    Paramount started building tandems in 1969. Prior to this time, only special team tandems (like Olympic bikes) were made.

    Serial Numbering: The first phase started in early 1969 and continued to the middle of 1970. It consisted of the following fields:

    • Month Code: This one letter code corresponds to the month with A=January, B=Febuary and so on. Because I is not used, September=J and December=M.
    • Year Code: This two digit code is the last two digits of the year – 69 is 1969.
    • PT:This code indicated a Paramount Tandem.
    • Sequence Number: This three digit number represents the nth frame and/or fork scheduled during the month.

    For example E69PT109 was a Paramount Tandem built in May of ’69. It was the 9th tandem of the year.

    The second phase started in Mid-1970 when Schwinn started using the standard numbering system (and probably a common bottom bracket) with the company’s mass production. For example, FF018524 was built in June of 1970, serial number 018524.

    All Paramount tandem production had ceased by the end of 1979.