YOu have to snap the rebound adjuster rod of of the adjuster in the f4 cap , then reinstall the adjuster . I added some epoxy and then filed the rebound adjuser off on the ourside just for looks .
You also need the conical washer out of the f4 that sits on top of the spring. The only mod needed to the xx is to cut your spaceer maybe 20 to 27 m shorter depended on where your want the preload start .
I just though of one thing , I have not checked for clearance at full compression, this may be a major issue
I will update when i figure it out in a day or 2.
I just checked there r clearance issues at full compression , so the adjuster wont work unless the damping rode is shortened
[b]Update, i could not find any cheap b12 caps so .. i made do wi the f4 ones
I just drilled out 25 mm of thread in the cap so the rod can screw up in 25 mm further . I got rid of the jam nut and put 2 5mm set screws cross ways in the cap bearing on the damper rod to keep it from unscrewing from the cap. Oh i welded up the hole in the cap for the rebound adjuster. thats about it. I have a range of 12 or 20 mm of preload adjustement .
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