From the Experimental Department.

It never pays to look in boxes or under benches, you never know what you might find. Usually it is something that you have been hiding from the wife for the last 15 years or perhaps that project that didn’t turn out just how you expected it to and working on the philosophy of “out of sight out of mind” you couldn’t be reminded of yet another failure.

But in my case it was a reminder of some ones unfinished idea that had it been completed would have resulted in something very unique. The subject, a set of engine crankcase patterns.  As a motorcyclist I know that we all have unfinished projects but this one would be quite special, a brand new “old engine”.

However, with practically no information on this project it makes one wonder what actually triggered the idea to create something different and new, and perhaps what the engine was going to be based around. I have been unable to find any reference in older manuals or magazines so can only conclude that the creator just put his magic thinking cap on.

So how special would this engine have been? Well the patterns indicate that it was going to be OHC with the cam, chain driven, the external webbing and perhaps the positioning of the oilways indicated an external oil pump which would seem to indicate possible prewar design ideas. The cylinder barrel would be alloy with the cylinder head through bolted from the crankcase for extra strength. And the cylinder head, well that could be anything, yet to be determined .

Speculation on capacity would be around the 250 to 350 capacity. The bore and stroke could be varied but my preference would be to create a short stroke 350 of about 76mm bore x 77mm stroke. However that is a long way off yet.

Now how far did this particular project get? There are no design drawings or sketches, or even doodles on table napkins (where  a lot of good ideas start). There may have been though because what there is are some excellent patterns ready to be put to use in the casting department. And to get to this stage surely there would have had to have been drawings. If not then there was a very clever person out there who just decided to “do it”!


The Patterns.

The next stage would be to cast up the cases. Finding a foundry that would be keen to do a one off, or perhaps two sets of cases has always proven difficult in the past so why should this be any different. Well there was no need because concealed in the bottom of the same box that had the patterns were a set of casings ready for the machining department.


The New Castings.   

The history of these parts is that they were an unfinished idea/project that came from the Gisborne area. I was given them about 15 years ago and told that it was the idea of a keen vintage racer possibly by the name of Steven Hall who may have raced a flat tank Norton at classic events who in the late 1980s decided to build his own engine. Sadly it wasn’t finished because Steven passed away.

So where to from here? Well a decision will be made as to how the barrel will be modelled and what design the cylinder head will be. Of course it will have to be OHC and, well that’s about it.

Thought will have to be given as to what to fit the engine into. My preference would be a pre war rigid frame, girders, with a 4 speed close ratio gearbox, most likely an Albion because they look old (think I have a spare one of those sitting on the shelf somewhere, or hiding under a bench).

But first there will be the machining of those crankcases, when time permits. And until then they will have to go back under the bench but hopefully not for another 15 years.

If anybody out there has any more history on the crankcases and what was proposed we would like to hear from you. We can be messaged through our Contacts Page.