BSA OHC Twin?

[Greybeard]

Text says: 1938 BSA OHC twin Prototype

[worntorn]

I've sent the photo to a good friend of mine who just happens to love building replicas of nonexistent 1930s OHC bikes.
He just sold two of his creations , a 1938 Velo Roarer and a 1938 AJS V4.
The AJS went to Czechoslovakia and the Roarer went to the Solvang Museum in California.
He's very interested in this BSA prototype.
Is it a 500?

[Swarfcut]

GB... An identical picture of this machine appears and is described in the early pages of Roy Bacon's "Twins and Triples." The book photo looks to be a selective blow up of this picture.

 Brief description....  Vertical Twin,  500cc, with a single overhead cam driven by bevel gears and shaft.  A Prototype Development Engine housed in a Silver Star Frame, with M Type cycle parts and girder forks.  Good for 100mph, as a standard road ready machine rather than a racer, not bad for 1939. So the text explains.

 Swarfy.

[Greybeard]

GB... An identical picture of this machine appears and is described in the early pages of Roy Bacon's "Twins and Triples." The book photo looks to be a selective blow up of this picture.

 Brief description....  Vertical Twin,  500cc, with a single overhead cam driven by bevel gears and shaft.  A Prototype Development Engine housed in a Silver Star Frame, with M Type cycle parts and girder forks.  Good for 100mph, as a standard road ready machine rather than a racer, not bad for 1939. So the text explains.

 Swarfy.

100mph, with those brakes?!

[Greybeard]

I've sent the photo to a good friend of mine who just happens to love building replicas of nonexistent 1930s OHC bikes.
....
He's very interested in this BSA prototype.
Is it a 500?

Swarfy knows more than me. I just copied the picture and caption from FB.

If your mate were to put a Kawasaki 650/800 engine in a girder frame he wouldn't be far off.

[Greybeard]

I knew if I searched I'd find something to show you!

[Swarfcut]

GB.... Warp Factor 6..... With that Headlight!       "The Red Windmill"     Must be a bit of a frantic ride!

 Swarfy.

[Greybeard]

GB.... Warp Factor 6..... With that Headlight!       "The Red Windmill"     Must be a bit of a frantic ride!

It could be made to look more reasonable though.

[worntorn]

I've sent the photo to a good friend of mine who just happens to love building replicas of nonexistent 1930s OHC bikes.
....
He's very interested in this BSA prototype.
Is it a 500?

Swarfy knows more than me. I just copied the picture and caption from FB.

If your mate were to put a Kawasaki 650/800 engine in a girder frame he wouldn't be far off.

That wouldn't be a big enough challenge for him.
Here's the Velo Roarer he whittled out of blocks of metal-

https://www.motorcycleclassics.com/classic-british-motorcycles/classic-velocette-motorcycles/1939-velocette-roarer-replica-zmtz18mazhur

[Greybeard]

...
Here's the Velo Roarer he whittled out of blocks of metal-
...

Jesus H Christ! He must have a very sharp whittling knife!
Does the machine get used?

A good read: https://goo.gl/5mVBPW

'Presently, he has it geared for 120mph at 7,000rpm. "For me to do 140 miles an hour on that thing, I'd be crazy!"'

[lawnmowerman]

What an amazing engine. If, like me, you are wondering what the internals look like then have a look at this engine cutaway drawing I have found https://www.flickr.com/photos/velton/4640552918

Jim

[Greybeard]

I cannot imagine having the confidence to decide; Yep, I'm gonna build that engine, at home!

[Topdad]

Let alone pilot it ,who'd you get to go pillion ????

[worntorn]

...
Here's the Velo Roarer he whittled out of blocks of metal-
...

Jesus H Christ! He must have a very sharp whittling knife!
Does the machine get used?

A good read: https://goo.gl/5mVBPW

'Presently, he has it geared for 120mph at 7,000rpm. "For me to do 140 miles an hour on that thing, I'd be crazy!"'

It did for awhile, however Dan just sold the bike to the Solvang Museum in California.
The owner there has a thing for Supercharged motorcycles
It will be on the rollers and started for demos from time to time.

He also sold his AJS V4 creation at Mecum auction.
He's given me the ( homebuilt of course) starter rollers from the Roarer, which I intend to use for starting my 1360 Vincent. Haven't tried them yet, it will be interesting
to see if they are up to it

Glen

[chaterlea25]

Hi Glen,
I found it kind of sad that Dan sold off his creations 
A Friend of mine was over in Canada a couple of years ago and met with Dan and his creations
Do you know he even made the carburetteurs himself   

John