Author Topic: Mystery 500  (Read 3528 times)

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Offline MRD

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Mystery 500
« on: 11 Aug 2010 at 15:24 »
Hi everyone
Over the weekend I was talking to a highly respected Douglas enthusiast, about an engine which looked very similar to a 2 3/4 hp but had a capacity of 500cc.
I do seem to remember an engine like this but for the life of me I can't find a picture of it.
Would it be possible if anybody could supply pictures of this machine. All I can remember is that the engine looks the same as a 2 3/4hp, with the tappets/ Valves at the same angle as the smaller engine. I think it was from the early 20's.
Regards   Martin 

Offline MRD

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Re: Mystery 500
« Reply #1 on: 11 Sep 2010 at 10:29 »
Hi everyone
Would my previous post on this be about the Williamson, which was built by Douglas. If so I would still be interested in any information or pictures.
It's one of those things that play on your mind, I've looked through the books I have and tried the internet even trying different search engines to no avail.
Any help would be appreciated
Regards           Martin


Offline Nick MW

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Re: Mystery 500
« Reply #2 on: 11 Sep 2010 at 22:13 »
Hello Martin,

I had a look online and found this (attached) picture on the VintageBike.co.uk site. Nothing else, just the picture, hope this helps.

Best regards, Nick



Photo courtesy of Vintagebike.co.uk
« Last Edit: 13 Sep 2010 at 22:22 by Dave »

Offline graeme

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Re: Mystery 500
« Reply #3 on: 11 Sep 2010 at 22:45 »
The Williamson engine was made by Douglas, but is much bigger than 500cc - I think 1000cc from memory.

Offline Dirt Track

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Re: Mystery 500
« Reply #4 on: 12 Sep 2010 at 06:46 »
G'day all
I wonder if we could be talking about.....Brough flat twin....ABC flat twin.....Coventry Victor flat twin......Humber flat twin.......Zenith (Bradshaw) flat twin.......Raleigh flat twin......or even one of the Continental makes. Could be a lot of possibilities for this 500cc flat twin.
Howard.

 

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