I mean they were "worn" but not "horrible"....there were some noticeable scuffs/grooves on the race where the rollers tended to sit. I've seen pictures on here of much worse. I asked if this was a "normal maintenance" item, something that should be replaced on somewhat of a schedule. Brendan said probably 20-25k miles if you wanted to be pro-active, but like me, most people only replace them when they start to be a problem.
Apparently PCW deals with customers complaining of wobbles pretty often, to which they suggest their "complete control" kit, which is new bearings, Progressive springs, 1" blocks, and an overall fork r/r (new seals and oil for me). The "vast majority" of the time this cured wiggles of any kind...high speed, low speed, deceleration, bumps/highway grooves, ect.
When they get loose, the top end is the first place it will manifest. For someone who doesn't really push it too hard in corners and seldom if ever tops 100, they may never notice any problems.
The wheel's rotational inertia(which at 100+mph is HUGE) is what keeps the wobble in check. Ever do that high school physics experiment with a bicycle wheel on handles? It would take a surprising amount of strength to move it about even with a modest spin. Your vmax wheel weighs probably 20 fold as much and is spinning 10 fold faster. It has a tremendous desire to stay in a perfectly straight line and resist quick changes of direction. The wobble is kept in check, at least temporairly, by the wheel's inertia. The wheel doesn't want to wobble. So even with 700lbs of bike/rider on the end of a 3ft lever aka the fork wiggling about, the rotational inertial quells the oscillations. The bearings are the critical link to allow that inertia to "hold" the bike steady at any speed. When that link gets play it it, the wheel is only "holding" the fork and handlebars, as normal imbalances such as vibration, wind, ect that would normally be overpowered by the inertia are allowed to act in the small amount of play, since even a thou or two of play in the bearing is magnified by the length of the bike stemming from it, it can turn into an inch or so of oscillation. The rear wheel fights this as well through the swingarm link. Eventually, if not quelled, the oscillation's inertia(700lbs wavering back and forth) will propagate on each wave, gaining force. Once it overpowers the wheel's inertia, you get a tank slapper where the handlebars oscillate between the two stops violently. People have instantly had their wrists broken by the force wrenching the handlebars...you're dealing with some pretty extreme amounts of energy. When it gets out of equilibrium, it wants to restore it as quickly as possible. If that new equilibrium is lying motionless on the side of the road with the rider tossed into the ditch, that's what it will be.
Without rotational inertial, two wheeled transport just wouldn't work. It's why riding a motorcycle very slowly is difficult...you have to do the balancing, instead of the wheels because they're not spinning fast enough to generate enough inertia to hold the bike up.
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