Triumph Frame and Engine numbers

Triumph engine numbers are stamped into the case just below the cylinder on the primary side. Frame numbers are stamped into the frame on the headstock also on the same side. Crooked stampings and unequal depth are common. Frame numbers match the engine number after 1950, but may not have the model designation, only the numbers.

1938 to 1949 models

Year and model shown as prefix to engine number. For example 8-T-33445 is a 1938 Speed Twin (later identified as “5T” instead of just “T”). Frame prefixes were-”TH” for early Speed Twin. “TF” for the T-100 and later 39/40 Speed Twin.

Year shown in engine number prefix with two figures. For example 40-5T-26445 is a 1940 Speed Twin. This practice followed religiously and some single prefixes may appear on postwar models. Frame prefixes were ‘TL” for the 3T up to 1948 and TC for 1949. TR5 for 1949 was followed by a ‘T” after the actual number. All other frames were TF. TR5 models did not have separate number series but ran concurrently with all other models. I.E. 112671 was last ’49 TR5 and I1 3386 the last ’49 5T.

Note: All Grand Prix T100′s have letter ”R” suffix following engine and frame numbers. TR5 models had separate number series; engines from 101001 to 106424, frames from TC11001-T to TC13107-T. Starting in 1950 frame and engine numbers were matching.

YEAR ENGINE NUMBERS FRAME NUMBERS
1946 FROM 72000 PREFIXED AS BEFORE
1947 FROM 79046 PREFIXED AS BEFORE
1948 88864 – 102235 TF 15001 – TF25000
1949 102236 – 113386 TF25001 – TF33615
1950 to 1979 models frame and engine numbers match
YEAR Unit 350/500 Pre Unit 500/650
1950 * from 100N
1951 * 101NA TO 15808NA
1952 * 15809NA TO 25000NA
THEN 25000 TO 32302
1953 * 32303 TO 44134
1954 * 44135 TO 56699
1955 * 56700 TO 70929
1956 * 70930 TO 82799
THEN 0100 TO 0944
1957 H101 – H760 0945 TO 011115
1958 H761 – H5484 011116 TO 020075
1959 H5485 – H11511 020076 TO 029363
1960 H11512 – H18611 029364 TO 030424
THEN D101 TO D7726
1961 H18612 – H25251 D7727 TO D15788
1962 H25252 – H27932 D15789 ON
YEAR Unit 350/500 Unit 650
1963 H29733 – H32464 DU101 TO DU5824
1964 H32465 – H35986 DU5825 TO DU13374
1965 H35987 – H40527 DU13375 TO DU24874
1966 H40528 – H49832 DU24875 TO DU44393
1967 H49833 – H57082 DU44394 TO DU66245
1968 H57083 – H65572 DU66246 TO DU85903
1969 H65573 – H67331 DU85904 TO DU90282
TRIUMPH ALPHA-NUMERIC PREFIX NUMBERING SYSTEM STARTED IN 1969

IN 1969 TRIUMPH INTRODUCED A NEW SYSTEM OF NUMBERING ENGINES AND FRAMES. THERE ARE TWO LETTERS, A FIVE DIGIT NUMBER, AND A MODEL DESIGNATION. THE FIRST LETTER REPRESENTS THE MONTH, THE SECOND THE MODEL YEAR, AND THE NUMBER WHICH BEGAN AT 00100 FOR EACH MODEL YEAR.

Please note

EACH MODEL YEAR STARTED IN AUGUST AND RAN UNTIL JULY OF THE NEXT YEAR. IF YOUR BIKE WAS MADE FROM AUGUST TO DECEMBER, IT IS A NEXT YEAR MODEL. FOR EXAMPLE: PD32232 TR6R WOULD BE A 1971 TR6R MANUFACTURED IN NOVEMBER OF 1970, AND KC16670 T120R WOULD BE A 1970 T120R MANUFACTURED IN SEPTEMBER OF 1969. THE LETTER “V” AFTER THE MODEL DESIGNATES A 5 SPEED GEARBOX.

Month of Manufacture Year of Manufacture
a - January c - 1969
b - February d - 1970
c - March e - 1971
d - April g - 1972
e - May h - 1973
g - June j - 1974
h - July k - 1975
j - August n - 1976
k - September p - 1977
n - October x - 1978
p - November a - 1979
x - December b - 1980

KNOWING THE YEAR OF YOUR ENGINE IS IMPORTANT WHEN ORDERING PARTS. IF YOUR ENGINE WAS MADE IN 1971 BUT IS A 1972 MODEL YEAR YOU MAY GET THE WRONG PARTS IF YOU ARE USING THE 1971 PARTS CATALOG. Please be sure of your engine year to insure correct orders.