Originally Posted by geo

Difference between 06 07 and later models is the link (117 compared to 119mm) and travel (less travel needs more spring to have have the same force at the end of travel).

Stiffer springs do not give a stiffer ride unless you have gone too far. It's a myth generated by the inexperienced. The opposite is usually the effect and simple math will show it to you.
Find the rate per inch, add the preload value and that is spring force about 1/3 travel. Add one more inch of rate to the first number and that is spring force at about 2/3 travel,,, and so on.

Advantage of stiffer springs in off road use is the fact they require less preload to support you and the bike. This helps when off throttle on stuff like downhill logs,rocks and roots. IE if you have 150 lbs of preload on a stiff spring compared to 250 on a soft spring, that is 100 lbs less force trying to whack the seat into your butt as the rear is unloaded.
The 100 lbs less preload from a stiffer spring carries on through the travel as the spring rate builds during compression and eventually ends up higher in rate at the end but is not stiffer all the way through. We only have about 3" of total spring travel anyway.
Win win in comfort and control if dampened correctly.

My 07 and me (230ish) like .47 in the front and 7.2 on the rear. Front is preloaded 6mm and rear is preloaded just 8mm to get the correct sags. Plush and supportive.
If I have my low speed compression adjuster set loose I can bump the shock bump stop on a log at walking pace. Definitely not oversprung.

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