Engine and Frame Numbers

Ariel

Year	Model	Engine Prefix	Frame Prefix (1939 rigid - spring)
1926	Heavyweight	P	P
1927	Heavyweight	V	V
1928	Heavyweight	W	W
1929	Heavyweight	H	H
1929	Lightweight	L	L
1930	Heavyweight	K	K
1930	Lightweight	M	L
1931	250cc	J	J
1931	350cc	A	J
1931	VB. VF.	N	N or K
1931	SB. SF. SG.	S	S
1931	4F 500	R	R
1932	250cc 350cc VB. VG. VH. SB. SG. 4F 500 4F 600	E B C D R T	B or D B C or D D T T
1933	250cc 350cc 500cc. 557cc 4F 600	DA BA CA TA	Y Y or E Y Y
1934	250cc 350cc 500cc.557cc 4F 600	EA FA GA UA	Y Y Y Y
1935	250cc 350cc 500cc. 557cc 4F 600	HA JA KA WA	Y Y Y Y
1936	250cc 350cc 500cc. 600cc 4G1000cc ohv 4F 600 ohc	AB BB CB DB XB	F F F P Y
1937	250cc 350cc 500cc. 600cc 4G1000 ohv 4F 600 ohv	AC BC CC DC101-615 EC	XF XF XF P P
1938	250cc 350cc 500cc. 600cc 1000cc 1000cc	AD BD CD DC616-650 DD	XG XG XG P P
1939	250cc 350cc 500cc. 600cc 4G & 4H 1000cc 4F 600 ohv	AE BE CE DE EE	M --- XG BX XG BX P AX P AX
1940	250cc 350cc 500cc. 600cc 4G, 4H 1000 cc 4F 600 ohv	AH BH CH DH EH & EEH	M --- XG BX XG BX P AX P AX
1941 - 5	350cc W/NG	BH, NBH, RBH	XG ---
1946 - 7	350cc 500cc, 600cc 1000cc 1000c	BK CK DH268, 273 - 6 DK	AP or BP --- BP --- P --- XP AX
1948	350cc 500cc, 600cc 1000cc 500cc Twin	AJ BJ CJ PT	BP BX BP BX XP AX DX CX
1949	350cc 500cc, 600cc 500 VCH 1000cc 500 Twin	DJ EJ CO FJ HT	RF SF RF SF COM SF GR GS HH HS
1950	350cc 500cc, 600cc 500 VCH 500cc Twin 1000cc	KL MN CO OP JJ	AB AC AB AC COM or AB AC GD LL TD CW
1951	350cc 500cc, 600cc 500 VCH 500 Twin 1000cc	RA RB CO RC RD	WA SA WA SA COM or WA SA WB SB WC SC
1952	350cc	TB	OA SD
1952	500cc, 600cc	TC	OA SD
1952	500 VHA	TCA	OA SD
1952	500 VCH	TR	OR ----
1952	500 Twin	TE	OB SE
1952	1000cc	TM	OC SV
1953	350cc NH 500cc VH 600cc VB 500cc VHA 500cc VCH 500cc KH Twin 500cc KHA Twin 1000cc4G MK.1 1000cc4G MK.2	XA XC VB (NOT XB) XD XE XF XFA XH XJ	AM AS AM AS AM AS AM AS MA (NOT AM) --- BW BS BW BS ---- ES EJ ES
1954	200cc LH 350cc NH 500cc VH 600cc VB 500cc KH 650cc FH 1000cc 4G MK.2 500cc HS 500cc HT	PA PB PD PE PH PJ PL PS PD or PT	---- KN KW KS ---- KS KW VS(NOT KS) BW KS ---- KS ---- KR ---- KSS KT or TF ----
1955	200cc LH 350cc NH 500cc VH 600cc VB 500cc KH 650cc FH 500cc HT 500cc HS 1000cc 4G	LA LB LC LD LE LF LJ LK GL	--- LS --- DU --- DU RF DU --- DU --- DU TF --- --- KSS or DUS --- PS
1956	200cc LH 350cc NH 500cc VH 600cc VB 500cc KH 650cc FH 500cc HS 500cc HT 1000cc 4G	ALA MA MB MC MD MLF MH MJ ML	MT PR PR PR PR PR PRS RT GM
1957	200cc LH 350cc NH 500cc VH 600cc VB 500cc KH 650cc FH 500cc HS 500cc HT 350cc HT3 1000cc 4G	BLA AMA AMB AMC AMD NLF NH NJ AMA NML	ST APR APR APR APR APR PRS RT RT GM
1958--9	200cc LH 350cc NH 500cc VH 600cc VB 650cc FH 500cc HS 500cc HT 350cc HT3 1000cc 4G	CBLA CAMA CAMB CAMC CNLF CNH CNJ TH CNML	CST CAPR CAPR CAPR CAPR CPRS CRT CRT CGM

Triumph

Twins from 1950 to 1969

Year	Unit 350 & 500	Pre-Unit 500 & 650
1950		from 100N
1951		101NA-15808NA
1952		15809NA-25000NA, then 25000-32302
1953		32303-44134
1954		44135-56699
1955		56700-70929
1956		70930-82799, then 0100-0944
1957	H101-H760	0945-011115
1958	H761-H5484	011116-020075
1959	H5485-H11511	020076-029363
1960	H11512-H18611	029364-030424, thenD101-D7726

BSA Unit Twins 1962-1965

	A50	A50 (Police)	A50C (USA)	A50CC (USA)	A50C & A50CC (UK)	A65	A65 (Police)	A65R	A65R (Rev counter)	A65T/R	A65L/R	A65SH	A65L & A65LC
1962 Engine Frame	A50-101 A50-101					A65-101 A50-101
1963 Engine Frame	A50-823/A50-2288					A65-1947 A50-2288
1964 Engine Frame	A50A-101 A50-5501	A50AP-101 A50-5501	A50B-101 A50B-101			A65A-101 A50-5501	A65AP-101 A50-5501	A65B-101 A50-5501	A65C-101 A50-5501	A65B-101 A50-5501	A65D-101 A50B-101	A65E-101 A50B-101
1965 Engine Frame	A50A-686 A50-8437	A50AP-121 A50-8437	A50D-101 A50B-4001	A50B-507 A50B-4001	A50DC-101 A50B-4001	A65A-1134 A50-8437	A65AP-267 A50-8437	A65B-334 A50-8437	A65C-1082 A50-8437		A65D-1742 A50B-4001	A65E-701 A50B-4001	A65DC-2158 A50B-4001