This is more an observation on the benefit of dry builds. Engine is a PGO 2T that I recently built, and more recently tore down after my buddy blew it up.
While inspecting everything, I noticed some unpleasant wear on the CVT end of the crankshaft. Previously, when swapping the variator, I'd observed aggressive spline wear on the fixed pulley half. I chalked it up to tasking it with delivering 4-6 times the horsepower it'd been designed for and ordered a couple of spares. This time, I found damage to the splines down by the starter gear. I suspected the ramp plate had shifted and started wearing the splines.
The crank and variator are performance parts capable of handling this sort of power, discounting my hypothesis that the fixed pulley was just too soft for the job. I was worried that I'd miscalculated when I fitted a Polini Ruckus/Zoomer variator and that the opening in the ramp plate was bigger than that of a PGO/Dio (spoiler alert, it wasn't).
Since the crank was out, I decided to stack everything up, torque the nut and check everything without a drive belt putting tension on it. I found that there is a tiny amount of slop which allows stuff to shift. Crap.
The plan is to create a small relief in the ramp plate to keep it located against the boss and to find a thicker washer to fit between the retaining nut and the kickstart boss.
I don't want to replace the crank since it's not my scoot (though I paid for the bike and the build, for the experience) and the owner is neither sensitive to the machine nor astute enough to identify a problem until it explodes; he just wants to be the fastest and show off. Since I'm sure it'll be back sooner than later, I think it's good enough for now.
The takeaway is to check everything before committing to the buildup, as the time invested is well worth avoiding buying performance parts again.