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General => Douglas Motorcycles - General Discussion => Topic started by: Lat Fuller on 25 Apr 2017 at 02:17

Title: 1912 Model "G" ?
Post by: Lat Fuller on 25 Apr 2017 at 02:17
To experts on early model 2 3/4 hp.
I was sent this picture of this 2 3/4hp which was being shown for sale at a the Stafford Bike show last weekend.
I am a recent comer to the Douglas scene (and I also live in Australia).   I cannot find any reference to this model anywhere and I am intrigued :  It has pedals, and the drive is on the left hand side.
I have no doubt that it is an original model, by the way it is made.   Also interesting to note its exhaust setup, and the way in which the manifold is connected to the heads (I have never some across this).
Any comments or further information would be appreciated.
Lat Fuller
Title: Re: 1912 Model "G" ?
Post by: Alan Cun on 25 Apr 2017 at 10:52
1912 13 were very big years for the Doug according to the book Best Twin. From what I can gather that type of alloy manifold was introduced on model D for 1910 and replaced by the screw on type later in 1913. From previous discussions on the forum the screw manifold was used on some race versions 1912.The crank cases with 2 piece timing cover also indicates right for 1912. From what I see it is what it claims to be.

regards Alan

 
 







Title: Re: 1912 Model "G" ?
Post by: cardan on 25 Apr 2017 at 11:09

Yes it's the 1912 single-speed model. Much was made of the switch from direct belt drive for the 1911 single speeder to the chain-cum-belt drive on the model you see here. The big advantage was that the front belt pulley could be much larger, so longer belt life and less slippage.

This particular example looks very nice, but has a few deviations from the original 1912 spec, perhaps most notably the later (but still veteran) AMAC carb instead of the rather lovely Douglas "salt and pepper" instrument. The double lever for the carb is also AMAC but even later - early 1920s.

But overall it looks like a very nice thing. I'd gladly find space for it!

Cheers

Leon
Title: Re: 1912 Model "G" ?
Post by: Lat Fuller on 26 Apr 2017 at 00:41
Thanks for that information.   Yes this looks to be a very nice bike.
Regards Lat
Title: Re: 1912 Model "G" ?
Post by: cardan on 26 Apr 2017 at 00:54

Come on, buy it and bring it to the National Veteran Motorcycle Rally in September! http://vvmccsa.org.au/nvr

Perfect!

(Excuse the free plug!)

Leon
Title: Re: 1912 Model "G" ?
Post by: Hutch on 27 Apr 2017 at 00:57
From the 1912 Manual
-Ian

(https://www.douglasmotorcycles.net/aa-files/images/hutch/2017/Douglas_Model_G_1912.jpg)


[Attachments converted to linked images. 01Jan22 -Doug, Admin]
Title: Re: 1912 Model "G" ?
Post by: Hutch on 27 Apr 2017 at 00:58
The 1912 engine and carby

(https://www.douglasmotorcycles.net/aa-files/images/hutch/2017/Douglas_1912_Engine.jpg)


[Attachments converted to linked images. 01Jan22 -Doug, Admin]
Title: Re: 1912 Model "G" ?
Post by: Hutch on 27 Apr 2017 at 00:59
Handle bar controls

(https://www.douglasmotorcycles.net/aa-files/images/hutch/2017/Douglas_1912_Handlebars.jpg)


[Attachments converted to linked images. 01Jan22 -Doug, Admin]
Title: Re: 1912 Model "G" ?
Post by: Hutch on 27 Apr 2017 at 01:02
Engine cross section - the 1913 and onward inlet port design seems a lot better than the 1912 one!

cheers
Ian

(https://www.douglasmotorcycles.net/aa-files/images/hutch/2017/Douglas_1912_Engine_Parts.jpg)


[Attachments converted to linked images. 01Jan22 -Doug, Admin]