Understanding preload

Hi just joined here...Seems like a cool forum  

So I've been reading Andrew Trevitt's book, Sportbike Suspension Tuning and trying to follow how front preload changes the geometry of the bike.

I understand that increasing preload compresses the spring in the fork and means that that spring will require a greater force exerted on it before it compresses anymore.

In my mind's eye, I can see a spring being squashed as preload is increased, so that's why I don't understand how increasing preload raises the front of the bike....Or does it?

I'm confused...Hope someone can help a guy out    

Welcome to the SR forum!

When you tighten the preload on the spring, it exerts more force against the weight of the bike/rider and any load on it. Thus, for the same load, it will force the suspension to extend more, resulting in the chassis riding higher.