Introduction to finding your bike’s frame number
In order to verify that the number on your vehicle registration paperwork match those your bike, you’ll need to locate the frame and engine number markings on your motorbike. This is easy enough, as long as you know where to look that is!
These are not always in the most obvious location and can often be hidden from view. You might also spot one of the various ‘red herring’ casting or part numbers which may be scattered around the bike and which are often mistaken to be the frame number.
Hopefully though with the help of this article you should be able to locate the correct, unique frame number on your AJS or Matchless motorbike in order to be able to verify it against what is recorded on your registration paperwork. The frame number is also known more officially as the “Vehicle Identification Number” or just “VIN” for short.
This article contains the following sections which you can jump to by clicking the appropriate title:
- Where NOT to look for the frame number
- Pre-1958 model frame numbers
- 1958-1959 model frame numbers
- 1960-1967 model frame numbers
- Engine and gearbox numbers
- Conclusions and your comments
Where NOT to look for the frame number
There are, apparently, many Matchless and AJS bikes out there that have been registered with the DVLA using the same “016117” frame number shown in the picture on the right. On my 1951 Matchless G3LS this is stamped into the top of the front down-tube. I initially, like many other people, mistook it to be the frame number. Actually it is just a casting or part number identifier from when the frame was made and hence is identical on many Matchless and AJS bikes, so beware!
The number shown in the picture is stamped onto the frame of my 1951 Matchless G3LS on the front down-tube, just in front of tank next to the top engine bracket. The circular loop cast into the frame on the left is the front side-car mounting.
The full code reads “+016117 M&B”. As far as I can tell this is a casting number (the ‘016117’ bit) and the manufacturers name or reference (the ‘M&B’ bit) as these components were not usually made in-house by AMC. It is definitely not the frame number!
The give away is the plus sign and the “M&B” additions, whereas the correct frame number should just be numbers with maybe a capital letter prefix (e.g. “A123456”) in some cases.
On some bikes, this part number is apparently raised (rather than stamped) which would mean it was cast into the frame and so must be the same on every frame from the batch (as they will all have come out of the same mould). On my bike though the numbers are definitely stamped (indented) into the metal, but either way they are not unique identifiers.
Pre-1958 model frame numbers
For the earlier Matchless and AJS motorcycle models made up until 1957, you need to do a little ‘digging’ under the saddle to find the frame number as it is not always in easy view. It depends a lot on what type of seat your bike has fitted; it’s much easier to see if you have a single saddle type, but more hidden by the longer two-person bench type.
The arrow in the figure on the right shows roughly where you should be looking. Standing on the right side of the bike (as viewed from the seated position), look up under the saddle to the back-end of the top horizontal tube just in front of where this joins the down-tube and the seat bolts into place. You’ll need a torch and the oil reservoir tank will also no doubt be right in the way!
If your frame is rusty, dirty or has been repainted it may actually be pretty impossible to read the numbers clearly from this angle. It’s actually much much simpler to just remove the seat (especially if it’s a long dual-seat type) to give yourself a clearer view. You’ll also be able to get in there to clean the relevant section of the frame, or look from different angles or under different lights in order to be able to make out all of the numbers.
The photo on the left shows the frame number stampings on my 1951 Matchless. Hopefully this should give you a pretty good idea of where you should be looking and the sort of thing you should be looking for. For reference, you can just make out the edge of the oil tank lid at the bottom of the picture and the back end of the petrol tank on the right.
1958-1959 model frame numbers
For the 1958 and 1959 Matchless and AJS models, the frame number location moved from under the seat to a more readily accessible location nearer the front of the frame. The arrow in the diagram on the right shows you roughly where you should be looking. The frame number should be stamped onto the right-hand side of the front down-tube, below where the forks attach but just above the top engine mount.
I can’t comment on the accuracy of this diagram as I’ve not needed to find the frame number on a bike from this period yet. However, the diagram is from the same source as the one above which I know to be correct so I have no doubt that this illustration is also accurate too.
1960-1967 model frame numbers
From 1960 onwards the engine number stayed in a similar position at the front of the frame, but moved slightly with the change over to a duplex frame with two front down-tubes.
Again the arrow in the diagram on the left shows you roughly where you should be looking, and also suggests that this is where the frame number should be on all of the so-called ‘Lightweight’ models.
Like before, stand on the right-hand side of the bike and look at the right-hand front down-tube, below where the forks attach but above the top engine mountings.
Engine and gearbox numbers
Now that you have hopefully found the frame number of your classic Matchless or AJS motorcycle, the other important piece of information which you’ll probably want to check against your log book is the engine number. This is much easier to find, but like the frame number there are a few casting number ‘red herrings’ to be aware of. I have therefore written a separate article on engine numbers which can be found here.
The engine and gearboxes are separate units on the earlier Matchless and AJS motorbikes and so the gearbox should also usually have it’s own unique identifying number. Whilst this isn’t normally recorded on the registration paperwork, it may be useful when applying for a dating certificate from the owners club or if you’re trying to confirm the completeness and originality of the bike. There is therefore also a separate article available on gearbox numbers which can be found here.
Well that’s about it really; there’s not much more to say about frame numbers that I can think of! If you have a later (post-1958) matchless or AJS I would welcome any feedback from you regarding the accuracy of the diagrams above for the 1958-59 and 1960-67 models as I have not yet been able to verify these myself. Please use the form below to leave me a reply.[sc:disclaimer]
I am trying to find out what year and model my bike is the serial #off of the frame under the seat is 42356 please help me thank you
Hi Larry. Your best bet is probably going to be the Owner’s Club dating service. They have access to the original factory records and can hopefully tell you everything you need to know about your bike from the frame and/or engine numbers. More details on this dating service can be found here:
I have just purchased a Matchless dirt bike ‘P11’ with matching engine
and frame numbers – 124835 it has I think a Norton Atlas engine.
Where can I obtain further information regarding year of manufacture etc.
Hi Tony. Check out the “AJS and Matchless Owner’s Club” and in particular their dating service (see link in the comment above). That should tell you everything you need to know about your new bike. James
Please send me all updates of ajs m16 1956 model
350 cc single cylinder petrol engine.
i. My name is Valur and I live in Iceland. I am trying to find out what year and model my bike is the serial of the frame under the seat is 4803. I hope you can help me out.
Is it a single or twin cylinder? any prefix letters in front or end of number? Paul
hi.it a silgle end of number
Hi, I have a 1950 Matchless G80 with a Lucas 467/2/MC tail light that I want to convert to LED, all help appreciated.
San Diego, California
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I have a matchless motorcycle the engine number is g80cs/5161 any . Idea on the year? Thanks
Hi Need help dating my Matchless G80S please Frame number is 73915 and engine number is 52G80S 21266. Hope you can help
Hi mate need help dating my AJS Frame number is A45612
Hello, I’m trying to check whether frame number 6535 could be a 1956 G80CS? Engine is definitely a G80CS but not sure if the frame matches. Thanks. Patrick
The frame should have a (c) after the. Umber or close to it
Hi,Can you please confirm that my frame number 5517CS is correct for a AJS 16 MC 1956.
I’m looking at buying a AJS model 20 from 1954, the frame number is A7236 does this look correct?
Thanks for any advice
I have frame # of 47858-52,can you tell me the bike & year this is from. thx
Dear James – Not an identification number question for which I apologise, but do you know of any Matchless G3Ls which were made in blue? – I saw a reference in which it was said some export models were sent out painted in other than black colours. Mine (circa 1955) in blue, is definitely its original colour, and came originally from Zimbabwe (then Rhodesia). There is no evidence of any black original paint.
Hi James I have a G9 from 1952. When manufactured Should the engine and chassis numbers be the same like with Triumph bikes?
Hi John. As far as I know, the engine and chassis number are NOT the same on AJS and Matchless bikes. At least they don’t match on either of my bikes and I am sure that’s how they left the factory! You can do a vehicle history check via the UK owner’s club who have most of the original factory records. Regards, James
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It’s simple survey filling. Even 10 bucks per survey (10 minutes duration).
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I need help regarding my G3 with duplex Frame. When using the center stand the machine doesnt move to an appropriate height (I bought the machine with the center stand currently fitted). I now always have to use wooden plates to get it positioned securely. My question: Is there a different type of center stand used for the duplex frame models compared to the older frame variants? If so, any hints would be very helpful (part number, suppliers etc.).
Hi Peter. Sorry, I can’t help with your problem, but I know a man who probably can! Give Steve a call at “AMC Classic Spares” in the UK (see here: http://www.amcclassicspares.com/).
Steve is a mind of information on everything AMC and also has a massive collection of used spare parts, so might be able to supply a correct / alternative stand for your bike. Hope this helps! James 🙂
Thanks for your quick reply – I will contact Steve to learn more about this issue …
Am looking for an estimated value for a matchless.
The only number I have found is C11249. If someone could help me, I would really appreciate it.
Hi I have picked up a matchless and I have no idea what year it is the frame number is 5822C or O
I found the title to a 1960 Matchless. VIN # 5226. in a box of motorcycle memorabilia It was owned at the time by J.R.Knapp, of Michigan. If you own this bike and would like the 1967 title to it, please let me know.
AHRMA & AMA Member
Regarding frame number or VIN: did they use a kind of id plate showing details such as frame number, engine size, machine model etc? I know from other bikes, that those id plates were often riveted or screwed onto a frame tube. Or was it just the number stamping you mentioned in your article?
Hi Peter. I think it’s really just the numbers stamped onto the engine and frame for most models and years. Pretty straightforward, nothing fancy. The machine dating service via the UK owner’s club will have more info, and copies of the factory records for most bikes. Regards, James
Thank you. I have already been in contact with the dating Service – everything fine. When it comes to an id plate, I will have to ask the German MOT people whether they want such a plate or not for official bike registration purposes …
Hello everybody. Can anyone tell me please, for whitch motorcycle is this frame nr 35…. Thanks.
I have just purchased a Norton/ Matchless with the following details
Engine number is N15CS/119803 which I believe is a 1967 Norton 750 Atlas
Gearbox number is MA639G which I believe is a post 1962 Matchless
Frame is stamped on the right of the head stock GA39CTOA692 which I have no idea about its origin.
Is anyone able to shed some light on this?
how about 2F0-201263 ON THE RIGHT SIDE OF THE FRAME ON THE TUBE WHERE THE FORKS BEARINGS /HEADSET TUBE RIGHT SIDE ITS A RIGED FRAME FRAME ONLY . ANY IDEAS ON WHAT IT IS?
Looking at a 1955 500 single, G80CS, although the engine stamping has the “C” after the serial number so it reads “G80S 1926 C”. This does not match the frame number: 5382C, should they match or is this from a later bike?
I have the original log book for an AJS which my late father rebuilt, the frame number o the log book is C72806 but from photographs I have the Index Mark and No does not match the bike. Any help would be gratefully received. Would be nice to pass on the log book to the current owner.
hi I have an 1950 ajs model 20 500cc twin serial 49639, I’m trying to find out the background of it because I need to title it ,were can find out if was not stolen ,or nothing crazy like that ?
every website I tried to enter the serial needs more numbers ..thanks,