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Discussion Starter #1 (Edited)
The Haynes book (chp.5 pp21) recommends rear preload on a 600SS as 14mm (a bit over .5 inch). Anyway I'm kinda lost here ...8[

This 14mm would be the "static sag" correct?

Thanks!
 

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Fully admit that I m just guessing here, but when a manual lists a "preload" number in mm, that usually means the amount that the spring itself is compressed from its free length, with the shock fully extended.

Tough to measure, because you need to get the wheel off the ground, with the bike supported by something other than the swingarm (e.g., steel bar through the swingrm pivot on jackstands), then with the shock fully extended back off the preload until there is no tension in the spring at all. From that spring length add preload until it is compressed by 14 mm, again, with the shock fully extended. This only works if it is actually possible to reduce spring preload to zero with the spring installed (not possible on all bikes). Or, just look up the unloaded spring length for your shock (sorry, don't know that number for your bike) and work from there.

Anyway, all of this is pretty moot. If you plan on using the spring that is on the shock, the only number that really matters is the rider sag - set that to 35 mm or so. Doesn't really matter what the "factory" preload setting is - you want the preload setting that gives the right sag for your weight.

If you find that the preload setting that gives you the desired rider sag (about 35 mm) leaves you with no bike only sag, that is usually a good sign that you need a stiffer spring. OTOH, if you set rider sag and end up with more than about 10 mm bke only sag, you could do with a lighter spring.
 
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