NEED ID's FOR 1920s MACHINES

[cardan]

Hi John,
I too am familiar with the "usual" 3-stud Blackburne - I have a c1921 8 horse (1000cc) twin in the shed. I spent years searching for the missing cylinder head (which as you will know contains the valves), and although I finally found one it was not before a few false starts that taught me that there are many similar-but-different Blackburne motors!!! I've also not seen a 3-bolt one-piece cylinder "in the metal" but let's guess some did exist.
I scored a copy of "Lost Motorcycles of the 1920s" for Christmas, and it has some details of the OEC range. Like other sources it lists Burman gearboxes for most of the models, but the new-for-1924 Villiers-powered lightweight apparently had a Sturmey Archer box.
Cheers
Leon

[ihmcallister]

Hi John,
Some healthy scepticism! I'm going to stick with Blackburne. In the photo we see is almost precisiely side-on (the bike is off the stand, and is leaning to the left) and slightly from the front. The side-on nature of the motor means we don't get to see the "plan" of the cylinder fins (below) except in subtle variation of the light (which I have no difficulty imagining). The slightly front-on aspect of the photo means we only see a bit of the outside flywheel in the gap between the frame, exhaust etc. (Since we are looking slightly down in the Neracar photo the flywheel looks higher - paralax.) 8 fins, widely-spaced valves, circular timing chest, valve lifter at 2 o'clock... perhaps there is another motor with these attributes?
The one-piece side-valve Blackburne cylinder was described as new in September 1922 when Marchant and Handley went long distance record breaking (7 hours/400 miles) at Brooklands on a 60 x 88 - 248 cc OK-Blackburne. I wonder if "our" bike is a 250 or 350?
Cheers
Leon

I am glad you experts are having such fun with this. I will trawl the archive and see if I can find a better pic!
I know Hilda owned an "Indian" at one stage, so she was quite a biker.
Cheers,
Mac.