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2024-06-11, 20:02:05
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2024-06-08, 18:30:04
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xman has two very nice 1950's machines available - a green 1950 mk4 and black 1951 mk5 - both in good condition and running well.


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2024-06-03, 08:23:05
For Sale
Duncan has just listed his green and cream 1957 Dragonfly for sale with spares and documents.


2024-06-02, 08:34:05
Parts avalable
alistair still has parts available - barrels, carburettor, castings - see all listings.


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EW cylinder base nuts

Started by tck, 01 May 2023 at 10:11

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I know Douglas threads are a law unto themselves so can anyone tell me what thread the seemingly 5/16 thread is for the three nuts that hold the EW 350 (1926) cylinder barrels on to the crankcase studs


        They are probably 5/16" X 25tpi. A near match is M8 fine (8mm x 1mm pitch).



The question is are you going to trust that to ride to Bristol and back ....

Has there been any discussion about why Douglas chose such odd thread counts ?
I know things were not yet entirely standardized - apart from Mr Whitworths & finest.
But ....

Can the LDMCC supply any of these. ?


I once suggested to Bill Douglas that his grandfather was an 'awkward old sod' for using bastard threads. Bill's immediate reply was, ' no he wasn't awkward, he was a 'canny Scot' who knew he couldn't get much for his bikes, so made sure you had to go back to him for your spares!'



nuts came, nuts fit !
I knew there must have been a reason for the metric system apart from measuring ICE engine capacities now I have found it. :-)


I remember my first TS ( purchased for 15 pounds..these were the days when UK bike shops had rows of now desirable but then unwanted British bikes out the back as Honda etc had arrived). Thread confusion!!! so I wandered into my local nuts and bolts place and the knowledgeable old boy at the counter ( they used to exist) produced his huge stock of thread gauges. An hour later, much head scratching, still nothing, no solution except the club's taps and dies sets.
The " they have to buy spares from Douglas" certainly applies.