I researched countless websites, some genuine gurus were found but they were few and far between amongst the jungle of internet idiots - you know the sort, the ones that know everything and have jumped over 17 more buses than you have! If they haven't then they know someone who has.
It wasn't until today that I stumbled across a particular website that finally made what I have been researching sync.
The picture below shows a graph with an ideal spring curve. It reaches full suspension travel (fully compressed) then returns to it's original length (free length) in the same time taken to fully compress. Rarely people have the 'correct' spring for their weight so I'm going to explain as concisely as I can what you can do about it.
TOO SOFT:
If the spring is too soft a lot of people think "it's okay, I'll just up the preload". WRONG. Increasing preload does nothing beside change the geometry and amount of travel in the forks. What needs to be done is increase the compression. Obviously there is a limit to the amount of compression you can add and this is down to the valve stack.
Changing the valve stack allows the compression to be firmer. When the compression is made firmer you also want to reduce the rebound damping (usually this is done by turning both compression and rebound adjusters the same way).
TOO STIFF:
If the spring is too stiff you will have the opposing problem to having springs that are too soft. In this case you need to reduce the compression damping and increase rebound damping.
THE SCIENCE:
A stiff spring is harder to compress than a softer spring, because of this you need less compression damping (compression damping can increase the force required to compress the fork springs). Because a stiffer spring contains more energy when compressed it needs more rebound damping to counteract it (therefore you increase rebound damping).
This enables the suspension to work nearly identical regardless of spring rate.
I hope this helps at least one interested person.
Thanks
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