I don't think there is a formula behind this due to the large number of variables. To keep development costs low, most large manufacturers build one-cylinder test engines for trying out various configurations. Once a maximum gain is found, the design parameter is frozen.
It will be made of steel and will not compress. You'll want to use Yamabond sealer. I'm going for .097" offset towards the front from the stock location. That should give it a millimeter or so Desaxe in the right direction. Ideally I would want about 2mm but I'm not ready to push it that far yet. They should be ready in about a month. It will raise the head about 1/32" but I have a .003" headgasket ring that will restore compression with .005" copper wire and plyobond around the pushrod tunnels and oil return (I've been using one 10 years without leaks).
You have mentioned moving the desaxe 'in the right direction', however I suggest that what is 'correct' depends on what is achieved when all the variables are adjusted to suit the change. The Commando 850 engine has surprised me - what is right seems so wrong - my Seeley 850 is beautiful in a race - that is strange. When I first began racing it, it was really weird - it took a bit to become used to the crank inertia. But it actually works very well.It will be made of steel and will not compress. You'll want to use Yamabond sealer. I'm going for .097" offset towards the front from the stock location. That should give it a millimeter or so Desaxe in the right direction. Ideally I would want about 2mm but I'm not ready to push it that far yet. They should be ready in about a month. It will raise the head about 1/32" but I have a .003" headgasket ring that will restore compression with .005" copper wire and plyobond around the pushrod tunnels and oil return (I've been using one 10 years without leaks).
If you ignore your racing irrelevance - to minimise the force on the heaviest thrust side of the piston the desaxe movement should be towards the front.
I would presume. There is not a single modern engine with a "negative" desaxe.
There's plenty of evidence and it makes sense in theory and it works in practice. Nobody questions it.
I am not questioning it. If somebody was going to remanufacture crankcases, they would need more than anecdotal evidence about the effects of changing desaxe. What Jim is doing with the base gasket, is a good thing. In reality, there is probably documented in formation on the effects. However with any motor, we never know the effects of a change until we work with it. The motorcycle is changed to suit its purpose, and the rider adapts to the bike. A rider who has ridden an excellent motorcycle, is often capable of improving a less perfect one. However Mike Hailwood began racing on a world championship winning Mondial 250, and was not good at conveying what needed changing to improve performance. Marc Marquez improves by crashing. Japanese motorcycles are good because the Japanese do their research. I suggest Joe Craig probably never told anybody anything. Norton were always about racing.
In this video, there is a photo of John Surtees working in the Norton factory in the 1960s -
