I spent the evening re-assembling the XRF8, which went surprisingly smooth
until I got to the rotary gear selector / shift actuator (not called so in the parts list, just to make it interesting). Despite
Dan Burkhart's excellent writeups and documentation of the later XRF8(w), there's precious little written about it's little PITA predecessor, so I had to do a bit of investigation.
What I found was that - regardless of how well I followed the assembly manual - the pins of the driver (HSA 623 "Gear Change") were not under full tension once I installed the right hand cone and cone anchor. Without this tension, the rotary gear selector won't snap back into 8th gear.
The instructions say the following:
Fit the cone ensuring that the two columns of the shift actuator are through the two slots of the cone. Turn the cone counterclockwise until two spots are parallel with the milling surface of the axle. Locate the cone anchor and screw the cone locknut.
If you follow the directions verbatim, you'll easily line up the cone anchor "spots" (more like a pair of depressions in the cone that engage with a thick, keyed washer [HMW 525 "Cone Anchor"]) with the flats on the axle, but you will NOT put tension tension on the spring (through the driver pins) when you do so. Consequently, the rotary assembly won't work - at best, you'll get some very minor tension half a turn through the rotation.
What it doesn't say is that you are supposed to turn the cone counterclockwise...
until tension is felt, then continue turning until the cone depressions are lined up with the flats on the axle. It takes a bit of finger force to make this extra half turn happen, and you'll need to be ready with the HMW 525 cone anchor already on the axle - it'll be easier to snap it in place (to lock down the cone) this way.
Ironically, the XR
D8 (XRF8 with a drum brake) manual has an error stating that the right hand cone needs to be turned
clockwise - but the hub internals are identical to the XRF8 and there's no reason for this. I tried it on the XRF8 and clockwise doesn't work.
Also, that extra washer I found inside the hub does nothing but add unnecessary wiggle room between the rotary assembly and the fulcrum arm ("lever") next to it. It almost seems as if it was put there as a kludge to reduce the possibility of the rotary assembly binding on the fulcrum arm. I'm just going to remove the washer and coat the contact area of the rotary arm with silicone oil.
Tagging
dweenk as he may be interested to know the progress. Hub gets reinstalled tomorrow...
-Kurt