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Ariel Engine and Frame Number Prefixes

Engine numbers, frame numbers, model designations and engine configuration for Ariel motorcycles from 1926 – 1965.

Letter codes are a prefix to the number which is usually 4 digits. Engine numbers are typically on the left hand engine case just below the barrel. Frame numbers are usually under the seat on rigid and plunger models and below the steering head on swing arm models. All numbers are stamped and indented.

Two strokes are at the bottom.

YR MODEL ENGINE FRAME BORE STRK CC/VALVES
RIGID SPRING
26 C, D P P 81.8 95 500 OHV
A, B P P 86.4 95 550 SV
27 C, D, E V V 81.8 95 500 OHV
A, B V V 86.4 95 550 SV
28 C, D, E W W 81.8 95 500 OHV
A, B W W 86.4 95 550 SV
29 C, D, E H H 81.8 95 500 OHV
A, B H H 86.4 95 550 SV
LB L L 65 75 250 SV
LF L L 65 75 250 OHV
30 A, B K K 86.4 95 550 SV
E, F, G K K 81.8 95 500 OHV
LF, LG M L 65 75 250 OHV
LB M L 65 75 250 SV
31 VB N N or K 86.4 95 550 SV
VF N N or K 86.4 85 500 OHV
SB sloper S S 86.4 95 550 SV
SF,SG sloper S S 86.4 85 500 OHV
LF J J 65 75 250 OHV
LB J J 65 75 250 SV
MB/MF/MH? A J 72 85 350 SV, OHV
4F R R 51 61 500 OHC SQ4
32 LF E B or D 65 75 250 OHV
LB E B or D 65 75 250 SV
MB B B 72 85 350 SV
MF, MH? B B 72 85 350 OHV
VB C C or D 86.4 95 550 SV
VG, VH C C or D 86.4 85 500 OHV
SB sloper D D 86.4 95 550 SV
SG sloper D D 86.4 85 500 OHV
4F/5 R T 51 61 500 OHC SQ4
4F/6 T T 56 61 600 OHC SQ4
33 LF ? DA Y 65 75 250 OHV
ME, MH BA Y or E 72 85 350 OHV
VE, VG, VH CA Y 86.4 85 500 OHV
VA, VB CA Y 86.4 95 550 SV
4F TA Y 56 61 600 OHC SQ4
34 LF, LH EA Y 61 85 250 OHV
NF, NH FA Y 72 85 350 OHV
VF, VG, VH GA Y 86.4 85 500 OHV
VA, VB GA Y 86.4 95 550 SV
4F UA Y 56 61 600 OHC SQ4
35 LF, LH HA Y 61 85 250 OHV
NF, NH JA Y 72 85 350 OHV
VF,VG,VH KA Y 86.4 85 500 OHV
VA, VB KA Y 86.4 95 550 SV
4F WA Y 56 61 600 OHC SQ4
36 LH, LG AB F 61 85 250 OHV
NH, NG BB F 72 85 350 OHV
VH, VG CB F 81.8 95 500 OHV
VB CB F 86.4 102 600 SV
4G DB P 65 75 1000 OHV SQ4
4F XB Y 56 61 600 OHC SQ4
37 LH, LG AC XF 61 85 250 OHV
NH, NG BC XF 72 85 350 OHV
VH, VG CC XF 81.8 95 500 OHV
VB CC XF 86.4 102 600 SV
4G DC101-615 P 65 75 1000 OHV SQ4
4F EC P 56 61 600 OHC SQ4
38 LH, LG AD XG 61 85 250 OHV
NH, NG BD XG 72 85 350 OHV
VH, VG CD XG 81.8 95 500 OHV
VB CD XG 86.4 102 600 SV
4G DC616-650, DD651- P 65 75 1000 OHV SQ4
4F DD P 56 61 600 OHC SQ4
39 OH, OG AE M 61 85 250 OHV
NH, NG BE XG BX 72 85 350 OHV
VH, VG CE XG BX 81.8 95 500 OHV
VA CE XG BX 81.8 95 500 SV
VB CE XG BX 86.4 102 600 SV
4G, 4H DE P AX 65 75 1000 OHV SQ4
4F EE P AX 50.4 75 600 OHV SQ4
40 OH, OG AH M 61 85 250 OHV
NH, NG BH XG BX 72 85 350 OHV
VH, VG CH XG BX 81.8 95 500 OHV
VB CH XG BX 86.4 102 600 SV
4G, 4H DH P AX 65 75 1000 OHV SQ4
4F EH & EEH P AX 50.4 75 600 OHV SQ4
41-5 W/NG BH, NBH, RBH XG 72 85 350 OHV
46-7 NH, NG BK AP,BP 72 85 350 OHV
VH, VG CK BP 81.8 95 500 OHV
VB CK BP 86.4 102 600 SV
4G, 4H DH268,273-6 P 65 75 1000 OHV SQ4
4G DK XP AX 65 75 1000 OHV SQ4
48 NH, NG AJ BP BX 72 85 350 OHV
VH, VG BJ BP BX 81.8 95 500 OHV
VB BJ BP BX 86.4 102 600 SV
KH, KG PT DX CX 63 80 500 OHV Twin
4G CJ XP AX 65 75 1000 OHV SQ4
49 NH, NG DJ RF SF 72 85 350 OHV
VH, VG EJ RF SF 81.8 95 500 OHV
VB EJ RF SF 86.4 102 600 SV
VCH CO COM SF 81.8 95 500 OHV
KH, KG HT HH HS 63 80 500 OHV Twin
4G FJ GR GS 65 75 1000 OHV SQ4
50 NH, NG KL AB AC 72 85 350 OHV
VH, VG MN AB AC 81.8 95 500 OHV
VB MN AB AC 86.4 102 600 SV
VCH CO COM,AB AC 81.8 95 500 OHV
KH, KG OP GD LL 63 80 500 OHV Twin
4G JJ TD CW 65 75 1000 OHV SQ4
51 NH, NG RA WA SA 72 85 350 OHV
VH, VG RB WA SA 81.8 95 500 OHV
VB RB WA SA 86.4 102 600 SV
VCH CO COM,WA SA 81.8 95 500 OHV
KH, KG RC WB SB 63 80 500 OHV Twin
4G RD WC SC 65 75 1000 OHV SQ4
52 NH, NG TB OA SD 72 85 350 OHV
VH, VG TC OA SD 81.8 95 500 OHV
VB TC OA SD 86.4 102 600 SV
VHA TCA OA SD 81.8 95 500 OHV
VCH TR OR —- 81.8 95 500 OHV
KH, KG TE OB SE 63 80 500 OHV Twin
4G TM OC SV 65 75 1000 OHV SQ4
53 NH XA AM AS 72 85 350 OHV
VH XC AM AS 81.8 95 500 OHV
VB VB AM AS 86.4 102 600 SV
VHA XD AM AS 81.8 95 500 OHV
VCH XE MA 81.8 95 500 OHV
KH XF BW BS 63 80 500 OHV Twin
KHA XFA BW BS 63 80 500 OHV Twin
4G MK.1 XH —- ES 65 75 1000 OHV SQ4
4G Mk.2 XJ EJ ES 65 75 1000 OHV SQ4
54 LH PA —- KN 60 70 200 OHV
NH PB KW KS 72 85 350 OHV
VH PD —- KS 81.8 95 500 OHV
VB PE KW VS 86.4 102 600 SV
KH PH BW KS 63 80 500 OHV Twin
FH PJ —- KS 70 84 650 OHV Twin
4G Mk.2 PL —- KR 65 75 1000 OHV SQ4
HS PS —- KSS 81.8 95 500 OHV
HT PD or PT KT or TF —- 81.8 95 500 OHV
55 LH LA LS 60 70 200 OHV
NH LB DU 72 85 350 OHV
VH LC DU 81.8 95 500 OHV
VB LD RF DU 86.4 102 600 SV
KH LE DU 63 80 500 OHV Twin
FH LF DU 70 84 650 OHV Twin
HT LJ TF 81.8 95 500 OHV
HS LK KSS,DUS 81.8 95 500 OHV
4G GL PS 65 75 1000 OHV SQ4
56 LH ALA MT 60 70 200 OHV
NH MA PR 72 85 350 OHV
VH MB PR 81.8 95 500 OHV
VB MC PR 86.4 102 600 SV
KH MD PR 63 80 500 OHV Twin
FH MLF PR 70 84 650 OHV Twin
HS MH PRS 81.8 95 500 OHV
HT MJ RT 81.8 95 500 OHV
4G ML GM 65 75 1000 OHV SQ4
57 LH BLA ST 60 70 200 OHV
NH AMA APR 72 85 350 OHV
VH AMB APR 81.8 95 500 OHV
VB AMC APR 86.4 102 600 SV
KH AMD APR 63 80 500 OHV Twin
FH NLF APR 70 84 650 OHV Twin
HS NH PRS 81.8 95 500 OHV
HT NJ RT 81.8 95 500 OHV
HT3 AMA RT 72 85 350 OHV
4G NML GM 65 75 1000 OHV SQ4
58-9 LH CBLA CST 60 70 200 OHV
NH CAMA CAPR 72 85 350 OHV
VH CAMB CAPR 81.8 95 500 OHV
VB CAMC CAPR 86.4 102 600 SV
FH CNLF CAPR 70 84 650 OHV Twin
HS CNH CPRS 81.8 95 500 OHV
HT CNJ CRT 81.8 95 500 OHV
HT3 TH CRT 72 85 350 OHV
4G CNML CGM 65 75 1000 OHV SQ4


Note- 1941-5, 350 W/NG. Some of the machines made for the Royal Navy had engine prefix letters NBH, and some of the machines made for the Royal Air force had engine prefix letters RBH. There was no record of this in the Despatch Books. In both cases the numbers were in the main BH sequence.

Ariel Two Stroke engine and frame prefix and suffix letters.

Note:- the two strokes all left the factory with the engine number the same as the frame number. One series of numbers was used for all the two strokes, prefixed T-,the model being indicated by the suffix letter.

/A = Early Leader
/B = Late Leader
/S = Early Arrow
/T = Late Arrow
/G = Arrow SS
/H = 200cc Arrow

Early Leaders and Arrows ( /A and /S ) are those up to and including 17440.
Late Leaders and Arrows ( /B and /T ) are those17441 and higher.
The earliest Arrow T- 8701/S
The earliest Arrow SS T- 20384/G
The earliest Arrow 200cc T-33701/H

This list originaly compiled by Roger Gwynn and Ralph Hawkins in September 1989, corrections to February 1993.

Merged in model letters and bore/stroke info from Accessory Mart.

All reproduced with permission.

Ariel tended to mix things around a bit so the line from one year to the next is not clean, but was around August. For definitive dating of your machine contact the AOMCC or Draganfly. For a small fee they can look up their microfiche copy of the factory despatch books. Each bike received a handwritten entry with other info included such as special options and date of despatch and where to. That’s how I know my bike’s birthday is May 31st!

2 Responses

  1. I recently purchased a 500 single. The engine and frame numbers match, W2821. It appears to be a 1928. How do I determine if it is a C D or E model? Are reprints available for the overhaul manual? I found a 1933 manual, will it be relevent, or not? Thanks for the good Info. Ted

    1. I don’t think the general maintenance stuff would have changed much between 28 and 33 so the manual will be of some use. I’m not very knowledgable about the pre-war machines. I recommend you contact Draganfly http://www.draganfly.co.uk or the UK owner’s club to get a dating certificate – they have copies of the factory dispatch books which will have the specifics for your machine.

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