As I mentioned earlier, arguably the most interesting of the early OHV Douglas racers was the four-valve-per-aluminium-cylinder machine that appeared at the Weston-super-Mare in September 1919. The Motor Cycle, 4 September 1919, described it thus:

"A new racing Douglas, with F. G. Ball as the rider, had an engine with aluminium cylinders and four valves in each head - two inlet and two exhaust - each pair being operated by a single overhead rocker and oblique tappet rod from the timing case. The machine had evidently not been tuned to its fullest pitch, according to the results gained in the events."

Les Bailey rode a 1914-TT-style machine at this event, and defeated Ball in all events. The eight-valve machine was short-lived, perhaps because of its rather "veteran" cylinder/head design, where the ports were cast integral with the aluminium cylinder and the valves (presumably) dropped in from the top together with their seats and springs. The seal between the parts must have been difficult with the different expansion between the aluminium and iron/steel.

There is a photo of the eight-valve engine in Clew (incorrectly dated as 1913 in my 1st edition), but I can find no description of it in the various Douglas books I have. Is the Clew photo period, or did the engine survive? Indeed have any of these early OHV Douglas engines survived?

Cheers

Leon

I'm back looking at EWs for sale, I've been distracted with a few other projects- finding a dolls head box to replace the Burman box on our 16H, isolastics on a Commando, new con rod and piston on newer mx bike, crankshaft oil seals on an RD250 and re assembling My 70s Husqvarna wr250- most of all this is work in progress... still!
I looked at the EW for sale at Tiermans and it was ok but needed too much work to make tidy- tank and frame needed re painting, rear wheel needed restoring, decomp missing etc. It looked a good usable bike but I wanted something more presentable and I really could do without another project.
I saw this on Car and classic but taking into account it needs parts re plating It again seems too pricey.
I may go and look it nonetheless.

https://www.carandclassic.co.uk/car/C1025866

Have a look on eBay - see link below

https://www.ebay.co.uk/itm/Amal-monobloc-375-7-13-16-carb-Douglas-dragonfly-twin-1955-59-used/323521944184?hash=item4b53691a78:g:2HYAAOSwSwhbgYKn

Swinging Arm wanted for Mk V project

The front hub I wanted is now found just a Mk swinging arm required

Kevin Cunniff 0131 555 4145

The Weston-super-Mare report, from Motor Cycling 7 Oct 1913:

"A very interesting machine was the new 2 3/4 h.p. overhead-valve Douglas racer, which was ridden by A. Alexander. The inlet and exhaust pipes are of very large diameter, the valves themselves being carried in the heads. It will be remembered that we gave particulars in July last. The valves are operated by neat adjustable tappets, the upper ends of which fit into cupped rocker arms. The crankcase release lubricates the overhead valve gear by blowing on to it. Lubrication is by drip feed to both cylinder walls. The radiating flanges are very deep and the frame is slightly longer than the standard 2 3/4 h.p. models. The machine did very well in its first heats, but the gear could not be changed in the final, and in the end a broken chain put Alexander out of the running."