Does anyone know if Norton ever reserected the four cylinder motor idea that ( from what I understand) spawned the featherbed frame? And why didn't they continue with the one the suposedly built. The picture on page 20 of the book by Dennis Howard has a picture that looks like a double overhead cam water cooled ( or is that a oil cooler ) four. I remember reading about this story years ago but the connection from thought to memory is a bit lost in my old age.

The reason it never appeared, or raced, is that it was never finished.

You may recall from the history books that bikes had a slump in sales in the early mid 1950s - and Nortons was a victim of that as much as everyone else.
AMC (AJS Matchless) acquired Nortons about then, and the Norton race shop was a VERY expensive luxury that eventually had to go. So Nortons, and almost evryone else, pulled out of GP racing at the end of 1954. The four project only ever got to a slave single cylinder unit built up for testing - and apparently first off it wasn't particularly powerful. It also had the oddity that the carbs faced forward, behind the radiator (yep, watercooling and DOHC) so that was going to be a problem if they'd got it on the racetrack.

Another of the could-have-beens of motorcycle history.
Not sure where the remains are now ?
Not enough to build a whole engine.

Info from a little orange booklet "Built for Speed" by Bruce-Main-Smith Publishing.

P.S. Remember that Nortons were quite a small manufacturer, so their racing achievements were quite remarkable given the incredibly small budget at the time - the phrase 2 men and a van comes to mind. These days, that wouldn't even cover the catering van costs of a minor GP Team ??

While I was at N-V, there was an attempt to do an OHC version of the Commando 750. Of course it was being done on the cheap and intended to use as many existing parts as possible. The head was re-done with overhead cams, bearing directly on "inverted bucket" valve actuation with clearances being done with shims ( a Rover 2000 design).

The really dumb thing was that they tried to use the existing camshft drive, down in the block and also to use the existing cylinder barrel design. The result was that the famshaft drive chain went from the sprocket down the bottom of the engine, up through the existing pushrod tube, across the camshaft drive sprockets and back down the other pushrod tube.

The camshaft chain was about 34 inches long! It turned out that OHC didn't do much for power output and the chain wore out so quickly, it affected the valve timing. Another example of how to waste money trying to save it.

gtsun wrote: ( from what I understand) spawned the featherbed frame?

The irish-men Rex and Crommie who designed the featherbed frame did it without any thought of a four-cylinder motor. In fact I read that they had a Triumph twin engine in the frame before a Norton lump was ever put in it.....

Norton had nothing to do with the featherbed frame, they simply bought the rights and design and used it, one of the few smart things they ever did. The McCandless brothers made all sorts of frames and gadgets to improve existing motorcycle design. If someone else had got to them and their frame before Norton did, Norton probably would have gone down the tubes and been discarded long before they did as they had nothing else outstanding to offer the world...

beng wrote: If someone else had got to them and their frame before Norton did, Norton probably would have gone down the tubes and been discarded long before they did as they had nothing else outstanding to offer the world...

I seem to recall seeing that they had in fact offered their frame to various other manufacturers, including BSA was it ?, who had all turned them down.
Shows what a forward thinking lot were back at the helm back then.
A bit of genius can go a long way....