Suntour Date Codes

Suntour may have started producing bicycle components in 1912, but it wasn’t until 1972 that they decided to start using date codes to indicate the year in which they were manufactured. The codes consist of two letters stamped on each component – the first letter representing the year and the second denoting the month.

On the left side of this page is a chart which shows the codes with the corresponding year and month. Such information has become exceptionally important for those who are building period correct bikes.

For example, a Suntour Mountech rear derailleur with the code “AF” on the back plate manufactured in June 1984.

The same or similar date code systems were later adopted by Shimano, Nitto, Sugino, Sansin, Sunshine an more.

CODEYEARCODEMONTH
O1972AJan
P1973BFeb
Q1974CMar
R1975DApr
S1976EMay
T1977FJun
U1978GJul
V1979HAug
W1980ISep
X1981JOct
Y1982KNov
Z1983LDec
A1984
B1985
C1986
D1987
E1988
F1989
G1990
H1991
I1992