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6th October 2006

Opinion: Matching Numbers

Have you ever wondered why people write 'matching numbers' on their adverts when they are selling a bike? David B Bullivant is puzzled by this tactic, and shares his confusion herewith...

When watching Saturday night TV here in Finland, many viewers hope for 'Matching Numbers.' They hope that the numbers on their Lotto coupon will match the numbers chosen at random by the machine in the TV studio - everyone has a dream. While there's life, there's hope…

Match. A noun and a verb - it has many meanings in English.

First of all it is something with which you can start a fire - it's called a match because at one end there is some combustible material which must be struck against something that 'matches it' and will cause the combustible material to burn; cowboys do it on their jeans, gangsters traditionally use a thumb nail, normal mortals may use any rough surface to get the sulphur and other material to flare into life. However a 'safety match' was invented which needs the coming together of two chemicals, stored separately - one in the match-head, the other in the side of the box, and these 'safety-matches' only ignite if these two parts come together abrasively. My goodness me, the dangerous 'strike-anywhere' matches can self ignite in the box if they are jiggled about and their heads become 'frictioned' against each other... the two parts needed to make a match work, match.

So, they match, or 'go well together'. Consider this - when Bill and Mary got married, people said it was a good match. This does not mean their relationship would be so full of friction that they would explode, but that they would 'go well together'. 'A match made in heaven'. Perhaps Bill and Mary were introduced to each other by a 'match-maker' - a person who introduces people so they will enjoy each other's company and may make a good match. The 'match-maker' does not spend his days in some satanic factory making matches for lighting cigarettes, pipes, cigars and to get the sauna stove going or to light the gas.

In the same way that the tie you select from the wardrobe will probably match the shirt you are wearing - reflect the same colour, or be of a certain design or hue that will 'go well with' your jacket, shirt… they match. While in the clothing department, consider the word 'suit' - this is a jacket and trousers which (these days) is made of the same material and pattern - they 'go well together' - the jacket 'suits' the trousers, and vice versa.

Your motorcycle will have tyres, the size and number of which will match the maker's specification for the intended use of the motorcycle. These days, such wheel and tyre sizes may even be noted in the registration document, or lodged in some officialdom - the numbers should match.

In sport; 'let's go to see the match between Manchester United and Southampton- it should be a good one…', indeed it should, because both teams are of the same quality, calibre: they each have the same number of players on the field, and the game will be very close, the result may be one goal to three, or six to seven, or fifteen to fourteen - a good match means the teams are evenly 'matched' - they 'go well together'. It is more than a 'game of football', it is a 'football match'!

If you go shooting, your ammunition should match the weapon you are using as well as the use to which you are putting it; duck-shooting is best done with a shotgun and using cartridges that give a good spread - no ducks fall if you try and hit them with a Colt 45 automatic and brass-bound, rimless ammo! The gun should match the use to which it is being put. And the feathers on a lot of ducks match their normal environment, making them hard to see on the ground.

A BSF nut will not match a millimetre-threaded bolt - they do NOT go well together.

When purchasing a replacement chain-guard, say, from a motorcycle parts supplier, it is hoped the drilled holes will line up with the brackets on the motorcycle; you hope the holes will match.

So what is all this nonsense about 'matching numbers' one sees in advertising for things like motorcycles for sale?

A number, yesterday.

Ah yes - it means the numbers match those displayed on the registration document. The registration number should match the number shown in the registration document. And you are in trouble if they don't! It should always be checked at point of sale - do the numbers match? The frame number is even more important and may land you in even deeper distress - always check that the frame number shown in the registration document matches that on the motorcycle you are interested in buying - it is worth checking even on new motorcycles, as well as older ones. The numbers match? Good. So why is 'matching numbers' mentioned in the advertisement - it is, after all, to be expected that the numbers do match.

Wait a moment. Perhaps the numbers do not match those on the registration computer. Perhaps someone has changed the engine and forgotten to tell the computer, or - shame - the frame has been changed…

And of course, in sensible countries such as Germany, there is a very good chance that the frame has been changed and you are not made aware of it. If you have the good fortune to inspect a motorcycle of German manufacture, you will perhaps be surprised to see that the frame number is not on the frame at all - it is on a small plate tacked onto the frame - only the small plaque bearing the motorcycle details is 'original', and even that may not be the case today because you can buy the tags with no numbers marked at all and inscribe on it the numbers of your choice, and tack the tag onto a spare frame you have lying at the back of the shed… It is the same with Ariel two-strokes - you may change the frame but retain the number if it matches the registration details and documents.

A matching number, yesterday.

The reason for this is not so that we can create new motorcycles from a pile of bits, but because in Germany (and remember, the Ariel two-strokes had frame details scratched onto a removable plate attached to the frame so the frame can be changed; the two-strokes were German powered, so there is ancestry there), if you have a road accident on your German motorcycle, there is a good chance the frame may have become distorted, bent, damaged and so on, and part of the insurance/registration system is that the said motorcycle has to be fitted with a fresh, brand-new frame … to which the old tag is attached, so maintaining continuity. The number of the new frame will match the number in the registration document - but it is a new frame. The frame is not thirty years old!

People who have anything to do with aircraft will assure you that the only original part on that sixty-year old DC 3 is the makers tag and the same numbers can be found in the aircraft registration/log book - but numbers are matching! That tag, bearing the maker's numbers is what identifies the aircraft. Yes folks, everything else on that DC3 is new, and it is no more an ancient aircraft than your old bits of Lego are!

Many single marque clubs based in the UK have access to the original maker's factory dispatch books. These books list the bikes that left the factory that day, the bikes are identified by frame and, perhaps, engine number. Remember, leaving the factory has nothing to with registration - registration happened when the motorcycle was purchased by the first happy owner - the only identity the machine carried until then is the frame number. A motorcycle that is booked as having left the factory in March 1951 might not have found a buyer until December 1952 - the registration date will be 1952, and the year of make is clearly 1951. By applying to your single marque club you can find when your particular motorcycle physically passed through the gates of the factory into the big, outside world. The single marque club will be able to match your frame number to a particular day, month and year.

A matching letter from a single-marque club, yesterday.
Triumph Hurricane bits on

The same single marque club may have the factory records, or copies of them - such records used to be lodged with the Metropolitan Police in London in the case of British motorcycles so that the police could check if a motorcycle was stolen, or its 'new' owner had the year and other details right. These records are now, largely, lodged with the Vintage Motorcycle Club in the UK, and are accessible to members. Engines went one way, the frame went another - but it is the frame that carries the motorcycle identification details. Some factories used different number/lettering series for the different models they made, even though the frames may have all been exactly the same - such frames allow an owner twenty, thirty years later to use an engine in that frame that fits - in such a case it is still an old motorcycle, perhaps now sold as a 350, whereas the original frame was wrapped round a 500.

So numbers may match the dispatch book records and may match the annual production runs in the factory - frame numbering was often year related. But the numbers match.

Some British factories had a habit of using the same number that was on the frame on a small part of the engine as the engine number, which was exactly the same as the frame number. 'The same as' is not the same as 'Matching'. Bill and Mary are a good match, but they are not exactly the same - those sorts of relationships should not be mentioned in a journal like this one! But consider the odd practice of adding the frame number to a small part of the engine. What does it mean twenty, thirty or a hundred years along the road? Engines wear out, even that half of the crankcase bearing the frame number may have been damaged and replaced. Does that make the motorcycle any less worthy, does it reduce its value?

The very part of the engine that carries the frame number may have suffered a 'rod through the cases' (not unusual with Triumph engines) and the crank cases may have been better off replaced by new ones both sides - a new pair - at least they wouldn't have leaked oil all over the garage floor. But suppose that the owner wants to be reminded of his frame number when he looks at the left hand crank case half? The crankcase would have had to have been carefully welded and re-machined, it may even had to have been replaced and the number may have been skilfully changed to be exactly the same as the frame number, but it is no longer original.

A matching number on a Triumph, yesterday. it just doesn't match any of the other numbers on this page...

Parts of engines wear out and have to be replaced. Here's a Triumph Tiger 100 that has been built from all new parts so that it looks just like the 1965 model the registration papers say it is - only two original parts can be found on the motorcycle - the frame and half a crank case casting! The numbers will match the registration document, the registration computer, the single marque club records, and the bill of sale, but it is no longer the original motorcycle, even though the frame number is exactly the same as that shown on the crankcase half…

Triumphs are specially mentioned, because unlike most other makers, that manufacturer used the same numbers on their frames and that crankcase half. Very few makers followed that system, so it has to be said that owners of those other makes cannot claim that their motorcycle frame number is exactly the same as the number stamped on part of the engine, but they have matching numbers in just as many other, more meaningful ways.

So it can be assumed that each and every motorcycle (and car) offered for sale has numbers that match. So why is it so pointedly stressed by advertisers? Where is the logic of stating 'matching numbers'? The seller might just as truthfully say his motorcycle has a petrol tank, or that his car has glass in its windows ... and the glass is the same shape on the left of the car as on the right - matching windows!

Some makers, BSA with the Redditch Sunbeam series being one, used model numbers in the identification of their frames and engines, initially. Later, for cheapness, saving money, making motorcycles to order (is this one going to be an S7 or S8?), they used only one model number on the remaining frames and engines - but according to our advertiser, the numbers do not match! But they do, even though they are apparently not correct. They are correct! Check them out via the single marque club...

But the question is not whether the numbers are exactly the same, which they may be on certain brands of motorcycle, but why is it such a big deal and what, pray, is being matched with what?

Or is this likely to cause instant combustion due to friction and violent matching explosions? As it is also said in English, 'Strike a light!'


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