I'm planning on replacing the springs in my forks with something more substantial and ideal for my weight. According to RaceTech, The F4i's stock fork spring rate is .66kg/mm

I'll be buying springs from SonicSprings.com and their calculator recommended .90kg/mm springs for me. (165lb w/gear and aggressive street riding style)

For fun, I decided to see how much a person would have to weigh for .66 to be ideal for even a "relaxed cruising/touring" style rider. SonicSprings only sells down to .70kg/mm so the calculation would not drop below that.

I found that a person would have to weigh 120lb w/gear for .70kg/mm spring to be sufficient for a relaxed pace. Therefore, at .66kg/mm the stock shock, to be ideal, would require a person to weigh less than 120lb with gear!

I find it almost comical how grossly inadequate the stock spring appear from this standpoint.

That said, I've had the stock spring for 3+ years and over 20k miles and they work. But now I'm on this suspension kick so I won't settle for what seems to be inadequate springs.

 

Its the reason people stress getting rebound valving at a minimum to go with the springs. I have the stock suspension about as dialed as its going to get so I can't wait to re-do my front end.