General Asian Serial Number Guide

This comprehensive guide decodes serial numbers from Asian-manufactured bicycles produced between 1970-1990, covering Japanese, Taiwanese, and Indonesian brands. Serial numbers reveal manufacturing date, production facility, and frame sequence numbers using alphanumeric codes specific to each manufacturer. Understanding these formats helps collectors accurately date vintage bicycles from brands like Fuji, Miyata, Bridgestone, Kuwahara, and dozens of others that dominated the bicycle boom era.

This information comes from Tom Marshall (T-Mar) of Bikeforums, a well-respected resource of bicycle history, especially from the bicycle boom era. According to Tom, this guide is “not necessarily comprehensive” but was compiled after many years of gathering information about serial numbers, verified by bicycle owners and people involved in the industry. Tom is confident in the deciphering of these serial numbers and interpretations below, and indicates the ones he is not sure of.

SOME BRANDS BUILT OTHER BRANDS

Another key point, there were some brands that contracted other brands listed below to build their bikes for them.  In this case, you find that two brands may have the same serial number format.  For example, this is the case with Univega who had Miyata build their bicycles for them.  These brands are cross-referenced.  Important to point out, all pre 1990 bicycles have the nationality in parentheses.

F indicates an alpha character designating the fortnight (i.e. A= weeks 1-2, B=weeks 3-4,….Z = weeks 51-52)

M indicates an alpha character designating the month (i.e. A = January, B= February,… L = December)

THE LETTER Y

Y indicates an alpha character designating the year .  However, the year that corresponds to a particular alpha character can vary significantly.  Please note, the specific convention will be listed under the manufacturer entry.

mm indicates two numeric characters designating the month (i.e. 01 = January, 02=February,….. 12= December)

y indicates a numeric character designating the last digit of the year (i.e. 1 = 1971 or 1981, 2 = 1972 or 1982, etc.). With such codes, you have to determine the decade based on frame characteristics, components, etc.

yy indicates two numeric characters designating the last two digits of the year (i.e. 81 = 1981, 82= 1082, etc.)

xxxx indicates a numeric characters designating the sequential frame number within a the fortnight, month or year.  In fact, this number string is typically four to six characters in length but can vary.

A BRANDS ASIAN SERIAL NUMBER GUIDE

AMERICAN EAGLE (USA): see Kawamura.

AMERICAN FLYER (USA): see Kuwahara.

APEX (USA): See Kuwahara

APOLLO (Canada): See Kuwahara.

A-PRO (Taiwan): Insuffcient data.

ARAYA (Japan): ARYMyxxxxx

AZUKI (USA): See Kawamura, Kuwahara, Giant.

B BRANDS ASIAN SERIAL NUMBER GUIDE

BIANCHI (Italy): See Hodaka, KHS, S(1)

BONTEKOE (Netherlands): see Miki

BRIDGESTONE BICYCLES

BRIDGESTONE (Japan): Myxxxxx & Fyxxxxx.
Grant Peterson, who was designer for Bridgestone starting in the mid-1980s, has stated that the alpha character is a month indicator.  However, apparent fortnight indicators a high as “T” have been seen as early as 1973.  This results in, the formats being easily confused with Miyata.

C BRANDS ASIAN SERIAL NUMBER GUIDE

CAMPANIA (?): See K(1), S(1), Y(1).

CENTURION (USA): See Fairly, Katakura, Matsu****a, Mikki, N(1), Tano, U(1).

CENTURION (Germany): see Merida, Java Perdana

CHIMO (Canada): Insufficient data.

C. ITOH (Japan): See Bridgestone.

CONCORD (USA): See Dodsun, Kuwahara.

CORSARO (USA): See Nissan

CYCLONE (Japan): Insufficient data.

CYCLE PRO (USA): See Dodsun, Kawamura.

D(1) (Japan): DyFxxxxx or DyMxxxxx.  Insufficient data to determine if 3rd character is a fortnight or month indicator.  Unfortunately, the identity is unknown but since format turns up primarily on Zebfrakenko and Zebra, it may be Kenko.

D BRANDS ASIAN SERIAL NUMBER GUIDE

DIAMOND BACK (USA): See Fairly, N(1), U(1).

DODSUN (Taiwan):  Unfortunately, there is insufficient data, but format appears to be DSBMymmxxxx(x) & DSym mxxxx(x) based on limited small size.

EDDY MERCKX (Belgium): See Miyata.

EMPEROR (Japan): Insufficient data.

FAGLUM (Sweden): See Miki

FAIRLY (Taiwan): Fymmxxx(xx)

FEDERAL (Indonesia); Insufficient data but starts with FC. First numeral may be year indicator. Also see Kuwahara.

FERRARE (Japan): Insufficient data.

FOCUS (Japan); See Araya

FUJI (Japan): P designates assumed production facility codes with known characters including F.G. I,J, K and M.

1971-1974: PyMxxxx, where years are based on the Imperial Japanese Calendar (i.e. 6 = Showa 46 = 1971, 7 = Showa 47 = 1972, 8 = Showa 48 = 1973, 9 = Showa 49 = 1974).

1975-1979: yyMxxxxx

1980-1989: PMyxxxxx

1984-1986 Special Series: Myxx(x)

GENERAL (USA): See Merida

GIANT (Taiwan):

1978-1986: Gmmyy on rear dropout.

1987-1989: GFyxxxxx

GITANE (France): See Nissan

GT (USA): See Hodaka, Fairly.

HIRAME (Japan): See Kuwahara

HODAKA (Taiwan): HyMxxxxx

HUNTER (?): See Yamaguchi

INTERNATIONAL (Canada ): See Bridgestone

ITOH (USA): See Bridgestone.

JAMIS (USA): See Fairly, Hodaka.

JAVA PERDANA (Indonesia): JPyFxxxx Due to insufficient data, fortnight indicator may be a month indicator.

JET (?); See Bridgestone.

JUPITER KING (Japan): See Sank.
i
K(1) (Japan): KyMxxxxx Same as 1980s Fuji format. Possible Fuji division or contractor.

KABUKI (Japan, USA): See Bridgestone, Nissan.

KAMRA (japan): See Kawamura

KATAKURA (Japan): KMyxxxxx Format easily confused with Kawamura.

KAWAMURA (Japan):

Pre-1975: KSxxxxxx

FROM THE YEARS 1975 TO 1987

1975-1987: PYxxxxx, where P indicates the market (A = Australia, C = Canada, E = Europe, K = USA 1975-1984 and late 1980s non-ferrous frames, W = USA 1985-1987). Y designates year where E = 1975, F= 1976,…. J=1980, then A = 1981, B=1982, … G= 1987. Easily confused with Katakura format.

KENSTAR (Taiwan?): Insufficient data.

KENT (Taiwan?): Insufficient data.

KHS (Taiwan): ymmxxxxx. See also U(1).

KING (USA?): Insufficient data.

KOBE (USA): Insufficient data but some may be Bridgestone manufacture.

KOGA-MIYATA (Netherlands); See Miyata

KUWAHARA (Japan): yy mmxxxx(x) Also see Federal.

LEEWORLD (USA): See M(1)

LOTUS (USA): See Pacific, Tsunoda, Yamaguchi.

M BRANDS ASIAN SERIAL NUMBER GUIDE

M(1): Unknown manufacturer, frame date code format appears to be MCAmmyy

MAIKO (USA?): See Kawamura, Kuwahara, Giant.

MARUISHI (Japan): Unknown, but format appears to be Y?xxxxx based on very limited sample size. Year indicators appear to be A =1971,1981,etc, , B = 1972, 1982, etc. Second alpha character appears to be either fortnight or month indicator.  Notably, easily confused with Tsunoda.

MATSURI (?): See Nissan.

MATSU****A/NATIONAL (Japan): yMxxxxx

MERIDA OF TAIWAN

MERIDA (Taiwan): Insufficient data, but format appears to be MyMxxxx(x) based on limited sample size.  Note that, month indicator could turn out to be fortnight indicator.  Also reported to use My??xxxx, where ?? is two letters.  To point out, some use a space or hyphen in front of xxxx number string. Easily confused with Miki , use country of origin decal, if present, to identify,

MIELE (Canada): See S(1).

MIKI (Japan): MyFxxxx

BF member Hummer believes 3rd caracter is a month indcator using A to M, with I omitted.

MIYATA (Japan):

1972-1984: Yxxxxxx, where A = 1972, B= 1973,….M= 1984.

1985-1989: YFxxxxx, where N=1985, O = 1986,…S=1990.

Format change occurred in late 1984, during model year change. Easily confused with Bridgestone.

See also U(1) for some late 1980s contract manufactured models.

MITZUTANI (Japan): Insufficient data.

MONGOOSE (USA): Insufficient data.

MOTIONCRAFT (?): See Miki.

N BRANDS ASIAN SERIAL NUMBER GUIDE

NIKO (USA); Niko was the private label brand of retail and mail order store Bikecology. Owner, Alan Goldsmith, also worked for Western States Imports (Centurion) . Interestingly, while I have no Niko serial numbers, 1980s Niko models do strongly resemble Centurion.  Therefore, owners are suggested to check the serial number formats of Centurion contractors.

NISHIKI (USA): See Araya, Dodsun, Fairly, Giant, Katakura, Kawamura, S(4)

NISSAN (Japan): YFxxxxxN based on limited size. All end with ‘N’, which is believed to represent Nissan Cycles, which appears on a sticker on some bicycles.  However, the first alpha character appears to be the year with C = 1980.

NASHBAR (USA): see Maruishi

NORCO (Canada): See Dodsun, Kawamura, Miki, Yamaguchi.

NOVARA (USA): See Fairly, N(1).

THE N DESIGNATION

N(1) (Japan): NyFxxxx Manufacturer unknown. Some members believe that the ‘N’ prefix designates National.  However, given that Panasonic and the Japanese manufactured Schwinns that came from Matsu****a/National do not use this format, it seems unlikely.   Moreover, there is evidence suggesting Tano, the major supplier to WSI/Centurion, though the format is different from that use in the 1970s.

BF member Hummer believes that the 3rd character is a month indicator with the 12 months being represented by A, B, D, E, G, H, K, L, M, N, P & S.

P BRANDS ASIAN SERIAL NUMBER GUIDE

PACIFIC (Taiwan): Pyxxxxxx

PANASONIC (Japan): See Matsu****a.

PARKPRE (USA): Insufficient data.

PEUGEOT (France): See Araya, Merida

PISCEAN (Taiwan?): Insufficient data.

R BRANDS ASIAN SERIAL NUMBER GUIDE

RALEIGH (UK): See Merida, Miki, N(1).

RENEGADE (?): See KHS

RENSHO (Japan): Insufficient data.

REX AND REX II HAVE INSUFFICIENT DATA

REX/REX II (Japan): Insufficient data. AKA Criterium Rex, the head badges on these bicycles denote Araya manufacture.  Surprisingly, they appear to be 1970s forerunners of the Araya branded bicycles of the early 1980s, but with a different serial number format.  For one thing, the format is similar to Bridgestone & Miyata, though frame characteristics, notably the distinctive seat stay caps, are different.

ROYCE UNION (Netherlands): Insufficient data.

S(1) (Japan): MSyxxxxx

S(2) (Japan): SyFxxxx

S(3) (Japan): sMyxxxxx

S(4) (Japan): Sy mm xxxx(x)

S BRANDS ASIAN SERIAL NUMBER GUIDE

SAINT TROPEZ (?): Insufficient data.

SAKAI (Canada): See Miki, Yamaguchi

SANKI (Japan): Symmxxxx based on very few samples, low confidence

SANWA (USA): See Dodsun. Miki

SAVOY (?): Insufficient data but based on head badge, appears to be a sister brand to Royce Union.

SCHWINN (USA): See Bridgestone, Giant, Matsu****a, S(3).

SCOTT (USA): See Fairly.

SEKAI (USA 1974-1983, Canada 1984-1990): See Dodsun, Fairly, Fuji, K(1), Matsu****a, Miki, Yamamguchi, Y(1).

SEKINE (Japan): Insufficient data, but format appears to be Ym(m) xxxx(x) based on limited sample size. Year indicators appear to be V= 1972 or 1973, W = 1973 or 1974, etc.

SENATOR (?): Insufficient data.

SHIMANO

SHIMANO (Japan): Shimano manufactured complete bicycles from September 1950 to May 1954.  As it turns out, these are extremely rare. After that, Shimano would commission frames to build up and use for displays at bicycle shows but these were generally high end models. Unfortunately, Most Shimano bicycles that surface have been rebranded by their owners. Consequently, there is too much variation in serial number formats to list.

SHOGUN (Japan): See Merida, Mikki, S(1), S(2), N(1), Yamaguchi.

SILK (Japan): See Katakura.

SKYWAY (Japan): See Bridgestone

SOMA (USA?): See Kuwahara.

SPECIALIZED (USA): See Giant, Miyata, S(1)

SPEEDWAY (USA): See Kuwahara

SR (?): See Araya, Miki.

STEVE BAUER (Canada): See Yamaguchi

SUCHIA (?): Insufficient data.

SUPERCYLE (Canada): See Bridgestone

T BRANDS ASIAN SERIAL NUMBER GUIDE

TAKARA (USA): See Fuji, Kuwahara, S(1), S(4), Y(1).

TANO (Japan): not yet decoded

TEAM CHANCE (Canada): See Hodaka

TSUNODA

TSUNODA (Japan): Unknown, but format appears to be YFxxxxx though correlation for Y has not been determined.  Interestingly, some members believe that Tsunoda was only a trading company and not a manufacturer.   Although, Lotus bicycles often have labels stating “Made by Tsunoda Japan” and similar statements can be found in Lotus literature.  As a result, it is easily confused with Maruishi format.

THE U DESIGNATION

U(1) (?): Uymmxxxxx Manufacturer unknown. These codes start appearing on Centurion and Diamond back models in the very late 1980s.  As a mater of fact, it is known that China Bicycle Company started supplying entry level models to Western State Imports at this time. Important to point out, this was just before acquiring WSI in late 1989 and this would appear to be the logical manufacturer but bicycles with this S/N format have been reported with Made in Taiwan labels and CBC was located in China.

U BRANDS ASIAN SERIAL NUMBER GUIDE

UNION (Netherlands): see Miki

UNIVEGA (USA): See Merida, Miyata, Dodsun, Giant.

UNIVERSITY (?): Insufficient data.

VENTURA (?): Insufficient data.

VISTA (USA): See Araya.

VOLKSCYCLE (USA): Insufficient data.

WORLD OF WHEELS (USA): See Kuwahara

Y BRANDS ASIAN SERIAL NUMBER GUIDE

Y(1) (Japan):Yyy mmxxxxx Manufacturer unknown but circumstantial evidence indicates it may be the pre-1980 Yamaguchi format.

Y(2) (Japan): YLyMxxxx Manufacturer unknown but may be for Yamaguchi aluminum frames as these typically surface on brands of aluminum frames.   Given that, some companies used Yamaguchi as a source for their aluminum frames.

YAMAGUCHI (Japan): YyMxxxx. To date there have 11 letter codes reported for the 3rd character (A though N, shipping D, I & J), so it is believed to be a month code. Of the 3 missing codes, D is probably the legitimate code.

Interesting to note, there has been some speculation whether Yamaguchi is the manufacturer for this format. In fact, some samples have been reported with Yamaguchi labels.

YOKOTA (Japan): Insufficient data.

ZEBRA (Japan?): See D(1).

Frequently Asked Questions About Asian Bicycle Serial Numbers

Where is the serial number located on Asian-manufactured bicycles?

Asian bicycle serial numbers are most commonly stamped on the bottom bracket shell, which is the cylindrical part of the frame where the pedal cranks attach. Check the underside of this area for stamped alphanumeric codes. The second most common location is the rear dropout on the drive side, where the rear wheel axle connects to the frame. Some manufacturers also stamped serial numbers on the head tube near the fork crown, the seat tube, or on both rear dropouts. If you cannot locate the serial number on the bottom bracket, systematically check all these alternative locations.

How do I determine what year my Asian bicycle was manufactured?

The year is encoded within the serial number using either alphabetic or numeric characters, depending on the manufacturer. For Miyata bicycles (1972-1984), the first letter indicates the year with A=1972, B=1973, continuing through M=1984. For Fuji bicycles (1980-1989), the third character represents the last digit of the year, so 0=1980, 1=1981, etc. Kuwahara uses the first two numbers to indicate the year directly (81=1981, 82=1982). Each manufacturer used different coding systems, so you must first identify your bicycle’s manufacturer, then reference the specific format listed in this guide to decode the year correctly.

What does it mean when different bicycle brands have the same serial number format?

Identical serial number formats across different brands indicate contract manufacturing relationships where one company built bicycles for multiple brand names. For example, Miyata manufactured frames for Univega, so Univega bicycles from this era use Miyata’s serial number format. Similarly, Kuwahara built bicycles sold under brand names including American Flyer, Apex, Apollo, and Federal. Giant manufactured frames for Schwinn. These manufacturing relationships were common during the bicycle boom era of the 1970s-1980s when demand exceeded individual factory capacities and companies specialized in different market segments.

Can I identify the manufacturer of my bicycle using just the serial number?

Yes, the serial number format often reveals the actual manufacturer even when the brand name differs. Cross-reference your serial number pattern against the formats listed in this guide to identify potential manufacturers. For instance, a serial number starting with “Y” followed by a fortnight indicator likely indicates Yamaguchi manufacture, regardless of the brand decal on the frame. However, some formats were used by multiple manufacturers, so you may need to consider additional factors like frame construction details, component specifications, and country of origin decals to make a definitive identification. The guide includes cross-references for brands that contracted manufacturing to help with identification.

What is the difference between a month code and a fortnight code in serial numbers?

Month codes use 12 letters to represent the 12 months of the year, typically A=January through L=December, though some manufacturers skip the letter “I” to avoid confusion with the number “1”. Fortnight codes divide the year into 26 two-week periods, using letters A through Z where A=weeks 1-2, B=weeks 3-4, and so on through Z=weeks 51-52. Fortnight codes provide more precise dating within the production year. Some manufacturers used consistent month coding (like Fuji), while others used fortnight coding (like early Bridgestone and Miyata). The specific coding system is identified in each manufacturer’s entry in this guide.

Why do some serial number formats show multiple date ranges for the same manufacturer?

Manufacturers changed their serial number formats over time as production systems evolved, factories expanded, or ownership changed. Miyata, for example, used one format from 1972-1984 and switched to a different format in 1985-1989 when they added fortnight indicators for more precise production tracking. Fuji used different formats across the 1970s and 1980s, with special formats for high-end signature series models. When a manufacturer’s entry shows multiple date ranges, you must match your serial number pattern to the correct time period format. Frame characteristics, component specifications, and catalog references can help determine which era your bicycle falls into when formats overlap.

What should I do if my serial number format does not match any listed in this guide?

Serial numbers that don’t match documented formats may indicate several possibilities. Your bicycle might have been manufactured outside the 1970-1990 primary coverage period of this guide, as formats changed significantly in the 1960s and again in the 1990s. It could be from a smaller manufacturer not yet documented in the guide, as this compilation is acknowledged as “not necessarily comprehensive” by its compiler Tom Marshall. Some entry-level or department store models used simplified numbering systems. Bicycles manufactured in countries outside Japan, Taiwan, and Indonesia may use entirely different systems. If you cannot match your format, document it carefully and share it with vintage bicycle communities, as collector knowledge continues to expand this reference.

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