Start numbers for H-DŽ serial numbers (SNs)

[Speeding Big Twin]

For a long time there has been confusion about start numbers for H-DŽ serial numbers (SNs) and last month I said I’d been thinking about initiating a new thread on the subject so that all info could be in the one place for future reference. Two decades in particular that keep cropping up are the 1930s and 40s and over the years I’ve asked many people why they (wrongly) think that SNs began at 1001 during that period. One person said his sources were hundreds of dealers but of course he never supplied any evidence to support his story. As for the rest, they too never posted any proof and I always wondered what their opinion was based on.

What then was the start number for production HarleysŽ for those two decades? It was 1000, apart from a certain military exception which I’ll get to later. And 1000 may have even been the start number for each engine family as early as 1915 models but the earliest factory document I have which mentions it relates to 1920–21 and I’ll come back to that in my next post.

In the beginning it seems H-DŽ engines received no SN so what was the first model year they did? Was it 1907? And if so, what was the start number? Anybody know for certain? In February I looked at a photo of an alleged 1907 model via Mecum Auctions but I didn’t have any 1907 model SNs to compare it with and I’d like an extremely clear close-up before giving an opinion on the SN.
Or was 1908 the first model year for a HarleyŽ SN to be stamped on the engine, as suggested by the document below? And if it was 1908, what was the start number?

BTW notice 1909 models are said to go to 4200 yet the same number was used at the beginning of 1910 models? Also 1910 models are said to go to 7600 but the same number was used at the beginning of 1911 models? Two at 4200 and two at 7600? Or factory typos?







More posts to follow.
Eric

[Speeding Big Twin]

As mentioned above, 1000 may have been the start number for each engine family as early as 1915 models although the document for 1908–1921 doesn’t provide confirmation. But there is confirmation about start number 1000 for 1920–21 in SDB 90. I’ve posted the first page of this bulletin on other occasions but here I’m posting part of the second page as well because it too refers to start number 1000 for 1920–21.








Anyone have other SDBs, or SBs, or Shop Dopes etc which address the start number(s) for the early years? If so please post them.

And regardless of when SN 1000 was first introduced for general production bikes, why was it used instead of 1001?

Again I don’t know the start number for 1908 which means some production models may have had SNs below 1000? And the same may have applied to some production models for 1907, if their engines received SNs?

During the 1911 model year SNs reached 10000 but it seems the factory then began again with a much lower SN and to set them apart from the previous 1911 models the letter A was added and this is referenced in the 1908–1921 document in my first post. But what was the lowest SN for a later-1911 production model? The lowest I’ve seen so far is 28+A so maybe the lowest was 100A?

Anyway at some point the factory introduced start number 1000 for production models while others such as racing bikes had SNs under 1000 and it may have been a deliberate plan to keep them and certain other non-production models below that number. But of course that left SN 1000 available so maybe that’s why the factory used it for production models.

More posts to follow.
Eric

[Speeding Big Twin]

Start number 1000 is also mentioned on some motor specification sheets. For example these partial spec sheets for some 1927 models.









But there was at least one exception for 1927 models and it related to the A-series and B-series.
For the previous year (1926) each engine family for general production models started at 1000, with most engines having the model year stamped in as part of the SN. But the 1926 A-series and B-series did not have the model year on the number boss. For example B1+++.







I don’t know why the model year was omitted from the number boss for the 1926 single-cylinder machines but the practice continued thru 1927. How do we tell the difference between 26s and 27s? One way is by how high the SN is. For 1926 singles they began at 1000 as mentioned above but for 1927 singles they began at 9000 as per these partial spec sheets.









More posts to follow.
Eric

[Speeding Big Twin]

Second attempt at this post.

Partial spec sheets for some 1928, 1929 and 1930 models.




















More posts to follow.
Eric

[Speeding Big Twin]

Partial spec sheet for some 1933 models.






Other documents mentioning the start number are layout sheets which may have first appeared for 1916 (?) models but the earliest two I have are for 1931 and 1933.








More posts to follow.
Eric

[Speeding Big Twin]

Factory photo of 35VLD1000 and a close-up of its SN. (Apparently this bike was used as a prototype.)








More posts to follow.
Eric

[Speeding Big Twin]

Partial spec sheets for some 1936 and 1937 models.











Factory photo of 37EL1000.






Regarding 1937 45ci production models, they too started at 1000 and over ten years ago the owner of engine 37W1000 posted photos of the SN on another forum. I could see nothing wrong with it and I advised the owner that the characters appeared the usual H-DŽ factory types for an early-37 model. (A lot of SN characters changed during the 1937 model year.)
He also posted photos of both belly numbers and they appeared authentic as well.


Partial spec sheet for some 1938 models.





More posts to follow.
Eric

[Speeding Big Twin]

Partial spec sheet for some 1940 models but obviously motors stamped UL are for the Model UL and not the Model US.






Anybody have motor specification sheets for any models and/or model years not shown above which address the start number(s)? If so please post them.


Factory photo of 40TA1000. The engine was for a Knucklehead trike that was said to have been used as a prototype and it seems to have been the only TA to receive a 1940 model SN.





But the TA engine wasn’t the same as the usual 1940 Knuckle engine so there may have also been an engine stamped 40E1000 or 40EL1000?

More posts to follow.
Eric

[Speeding Big Twin]

For the US Army at least sixteen 41TAs were built and this appears to be the SN from the first of them. I can’t see anything wrong with the characters, including the A which is the type I’d expect for an early-41 model. (During the 1941 model year the A changed from seriffed to sans serif and both types are visible in SNs of 41WLAs.)







Like the 40TA the 41TA was a Knucklehead trike although this time the SNs went as high as 1015. But again the engine wasn’t the same as the usual Knuckle engine so there may have also been 1941 model E-series and/or F-series Knuckleheads with SNs 1000–1015?
Anyone have a photo of an engine stamped 41E/EL/F/FL in the 1000–1015 range?

More posts to follow.
Eric

[Speeding Big Twin]

For 1942 models the start number was again 1000 for each engine family and the same can be said for 1943–1945 models apart from an exception regarding the WLA, with the 1943–1945 Model 42WLA SNs continuing on from 1942 SNs.

In the winter 2009 issue of The Antique Motorcycle there was a good article about H-DŽ SNs written by Herb Wagner. AMCA members can find that issue via the home site and on page 61 you’ll see a photo of an engine stamped 46WL1000.

Next are two pictures sometimes used as alleged evidence that SNs for the 1948 Model S did not start at 1000 because a prototype had been stamped 1001. (Notice no number boss.)








But here’s a layout sheet posted by Herb Wagner on the AMCA Facebook page earlier this year and it says the Model 48S did indeed start at 1000.





That is the third layout sheet I’ve seen, the others being for 1931 and 1933 which I posted above. If anyone has layout sheets for other years then please post them.

Another post to follow.
Eric

[Speeding Big Twin]

Another model year where there has been confusion is 1954. In 1977 the owner of 54KH1001 received a written reply from H-DŽ saying their records showed that his motorcycle was ‘the first one produced in 1954 of the KH series.’

But was the person at H-DŽ correct? If so, I wondered if more than one start number was used for 54 and it depended on engine family? I believe Big Twins for 54 started at 1000 but did the K-series for 54 begin at 1001? And if so, did the K-series also begin at 1001 for 52 and 53? If K-series SNs began at 1001 it seemed reasonable that the same start number was used for the SportsterŽ when it was introduced for 57 and I wondered if maybe H-DŽ decided then to change start numbers of other models such as Big Twins so every engine family started at 1001.

But apparently the 1977 reply from H-DŽ was not correct because Herb told me his notes taken from a 1954 layout sheet say: ‘All motors including KH, KHRM, KR, KRTT, KHK start with 1000 and continue consecutively.’

For 1955 and 1956 models the start number for each engine family remained 1000.

But apparently for 1957 models the start number did change to 1001. Why? I do not know. Anybody know for certain why the change was made? And what did they do with SN 1000 for 1957? As I mentioned above, some machines such as racing bikes had SNs under 1000 and it may have been a deliberate plan to keep them and certain other non-production models below that number. But of course that left SN 1000 available so maybe that’s why the factory used it for production machines. But that seems to have come to a halt as of 1957 models so what happened with SN 1000 that year? Was it not used for any bikes?

For 1958 and 1959 models the start number remained 1001.

For 1960–1969 models the even-odd (E-O) code was used and apparently for Big Twins that meant four start numbers. For 60, 64, 66 and 68 Big Twins it was 2000. For 61 and 65 Big Twins it was 1001 but for 63, 67 and 69 Big Twins the factory went back to 1000 although I do not know why. For 62 Big Twins it was 2001. Why four start numbers for Big Twins instead of two? I have no idea. I’ve seen mention of these four start numbers in certain publications but said publications aren’t factory. Can anybody post factory documentation or any other factory evidence of these four start numbers?

BTW, to this day you’ll find people who think the E-O code began in model year 1962 and sometimes the alleged proof they refer to goes as far back as the early-1970s. I’m also aware of someone who said the code began about mid-62 while a magazine published by the H-DŽ Riders Club of Great Britain in 2016 said the code started from late-62. But all references to 1962 are wrong because the E-O code did in fact begin with 1960 models. And it then remained in use through 1969 models. Also, although I refer to it as the E-O code I do not know what H-DŽ called it. Anybody have a factory reference to it?
Eric

[1939wl]

A lot of research there Eric.
Thank You for compiling all of this, and posting it in one place.
Very Informative.

[Speeding Big Twin]

Cheers. Many times in the past people have (wrongly) said SNs began at 1001 in the early years. Why? I do not know, as far as most of them are concerned. One person said his sources were hundreds of dealers, as I mentioned above, but where did the rest of those people get their info? And even after I showed them some of the proof I used in this thread there were a few who continued to say 1001.

But in future when the subject crops up I’ll post a link to this discussion and anyone who thinks SNs began at 1001 in the early years will be confronted by a lot more factory evidence to the contrary.
Eric

[duffeycycles]

Good stuff Eric !

[marksg]

Thanks for your work Eric. I am glad someone is doing it.