Author Topic: Identifying Douglas motorcycles- Part 2: 1920s and 1930s  (Read 29775 times)

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Offline Doug

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Identifying old Douglas motorcycles
Part 2: 1920s and 1930s (excluding 2-3/4 and 4hp)

Owners and folks finding an old Douglas motorcycle (or bits and pieces of one) often need to know how they may be able to identify the year and model.  What follows is a personal attempt to provide a guide to the codes and numbers that the factory put on the main parts of Douglas machines -specifically, frames, engines and gearboxes.  Supplemented with a description of salient features that in the addition/absence of the codes, might help also to identify a specific year, or indicate a mixture of parts. 

From about late 1925 onwards, Douglas brought out a range of new models; reflecting demand for more power and, towards the end of the decade, the great popularity of dirt-track riding.  The Dirt Track (DT) models were a great success, and road-going versions were produced for popular riding - and to allow the bikes to be ridden legally to and from speedway venues!  The current fastest classic sprinter around today is Henry Body's bored out DT 500 - with quarter mile finishing speeds above 110 mph, there's virtually no-one who can catch him, even on much more modern bikes.  These vintage DT and Speedway bikes are now extremely valuable, so if you have one, be sure you know what they are worth before parting with it!  The Douglas firm went through some rocky times during this period, which is reflected in the wide range of models - and their often extremely short production runs! 

The link below will take you to a page with additional information and tables to identify the various models and years.  These pages will be updated from time to time as additional information comes to light.  So note the version number near the top, and compare it to any copies you might have saved or printed.  There are also hyperlinks back to this post, and to Part 1 and Part 3 covering the rest of the Douglas range. 

The information in these tables has been collected from various sources: factory records, registers of extant machines, Douglas publications, articles in the London Douglas Motor Cycle Club magazine the New ConRod, and personal knowledge.  While every effort has been made to provide the most accurate information available, the information provide above is offered as a guide only.  It is not recognized as official dating data by any licensing authority.  The numbers and codes shown in these files are what appear to me to be representative of most of the machines registered as that model.  You may find them useful as indicators, but for final confirmation please do check with the experts in the London Douglas Motor Cycle Club (LDMCC), as I cannot accept any responsibility for any errors that may occur through the use of this information for identifying something that you find. 

If you have any additional information, corrections, or constructive criticism, the author would be pleased to hear from you. Please address your comments by e-mail or Personal Message using the link appropriate to your choice in the left block beneath the avatar. Alternatively, to make public comment  please use the Back button on your browser to return to the Topic Index and post a new topic by selecting the Start New Topic link at the top of the page.

If you have questions about a particular part or bike you are trying to identify, please use the Back button on your browser to return to the Topic Index and post a new topic by selecting the Start New Topic link at the top of the page.

-Doug K.

Copyright Doug Cross, Doug Kephart, April 2005

The Link:
Part 2: 1920s and 1930s (excluding 2-3/4 and 4hp)
« Last Edit: 19 Apr 2016 at 16:07 by Doug »

Offline Doug

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Re: Identifying Douglas motorcycles- Part 2: 1920s and 1930s
« Reply #1 on: 22 Oct 2006 at 01:56 »
Please note that the Identification of Douglas Models above has been updated. Correspondingly, the version number below the title in the linked "Part 2" has been indexed. If you have a copy of the tables, you may wish to replace it. You may notice a skip in the version numbers; they are indexed based on working copies which might go through several iterations before being released. The latest and greatest is what you see posted. Enjoy!

-Doug 

Offline Doug

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Re: Identifying Douglas motorcycles- Part 2: 1920s and 1930s
« Reply #2 on: 19 Apr 2016 at 16:08 »
Minor updates, new version posted.
Current version 4.8; previous version 4.6.

-Doug

Offline saluki42

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Re: Identifying Douglas motorcycles- Part 2: 1920s and 1930s
« Reply #3 on: 13 Mar 2021 at 16:10 »
Thanks Doug I'll amass all number and see if I can identify them, at the moment I can remember both engines numbers start EQ

Chris

Offline Doug

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Re: Identifying Douglas motorcycles- Part 2: 1920s and 1930s
« Reply #4 on: 13 Mar 2021 at 18:18 »
Chris,

EQ is your standard S5/S6/T6 crankcase. If you happen to have EQ1950, that would be the original engine out of my Greyhound (according to the logbook)!

-Doug