need help with these springs

[lnb001]

So i got my sonic springs in and spacers and was confused on the sag and preload.  My spacers are just over flush with the tops of the forks so that i barely have to push down with the cap to screw it back on.  I have .85 springs and the spacers I cut measured 4 7/8 inches.  I weigh 140 with gear give or take and do normal-aggressive street riding.  Any ideas?  Any help would be great!  Thanks.

-Lucas

P.S.  when i put my wheel and caliper back on, the wheel would not spin continuously like the front wheel on a bike, is that normal?  I can't remember how it was before i took the forks off.  when i push my bike around i can hear the caliper rubbing against the plate, if that helps...anybody else have that?  Thanks.

[GeeP]

4 7/8 sounds about right.  My guess is the springs vary slightly in length due to end grinding. 

In this thread I figure the spacer lenght of my Sonics Springs as 5.05"  I haven't verified static or dynamic sag figures at that preload though.  Frankly, for the kind of riding I do it doesn't matter.

The wheel will not spin like a bicycle wheel because of brake caliper drag.  Hearing a little caliper drag is normal.

[dgyver]

Preload for straight rate springs is typically 3/4". This about the same as the threads of the fork caps. So the spacer would be level with the top of the tube. This needs to be measured with no load on the springs.

[Y2K6GS500F]

I have mine .90 Sonics in with the spacers cut to 5.5 inches. This gave my a static sag of 1.4 inches with my gear on. With gear, I'm at about 205 lbs. Static sag is the amount the suspension changes from holding just the bikes weight, to holding the bike and your weight.

GS forks have 4.7in of travel (120mm). So in an ideal situation, you should set your static sag to about 25-35mm.

Hope this helps.

BTW, Here is a previous post about my install:

Ok, After testing various oil levels and spacer sizes, this setup seems to work best with the Sonic .90 springs, for my weight and size (5'10 @195lbs without gear, about 207lbs with helmet, boots, jacket, gloves etc..)

Total Spacer Size of about  5.65" or 143mm
(PVC cut to 5.5" and placed 1/8" thick washer on top- removable in case I lose weight  )

Fork Oil Level, as measured from top of fork tube to oil surface, 5.3" or 135 mm
(measured with forks compressed and springs, spacers, and washers removed -oil level increased about 3" with everything in)

This setup has me at a static sag of 1.4" or 35.5mm with my gear on.

The ride is 10x better than stock. It's firmer, but not at all harsh, and No more brake dive. 

Ok, now some advice:

1) Before you start, get some painters tape and wrap it around the handle bars where they meet the clamps. Mark on the tape where they meet the two halves of the cleamp. This will help you get the bars back on the bike in exactly the same place they were.

2) Measure twice, cut once. But, just in case you messed up cuts or want to try different lengths, Lowes hardware store has 5' lengths of 1/2" of schedule 40 PVC for about $2. If you want, pick up some 12mm washers while your there -for a little fine tuning of the spacer size.

3) If possible, use a miter box to cut the PVC. You want to get the cuts as straight as possible. I used one, and they still were not perfect. But, they were real close. The PVC seems to melt during cutting making it difficult. I suppose it's not a big problem, as the spring will conform a bit to meet the spacer.

4) Get some old towels and layer them over your tank and gauges, because no matter how careful you are, some oil will spill out when you remove the old springs. The towels also provide some cushion, just in case you drop a tool on the tank when working. Tools tend to get real slippery when you working around fork oil.


Hope this helps!