How to fix: Worn variator rollers: how do you go about it?

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Diagnosis confirmed: the variator rollers are worn or flat-spotted, which degrades the scooter's automatic transmission (sluggish acceleration, lower top speed, sometimes clunking noises). The variator is the heart of the scooter's CVT transmission: it continuously varies the gear ratio thanks to rollers (small weights) that, under centrifugal force, spread the variator's faces apart more or less as revs climb. The rollers are wear parts: they wear down, develop flat spots, and stop sliding properly, which keeps the variator from reaching its optimal ratio -- hence the loss of acceleration and top speed, and sometimes clunking on takeoff or deceleration. The fix: open the transmission cover (left side), remove the variator, and replace the rollers with a new set of the CORRECT weight (roller mass, in grams, is critical to how the transmission behaves: stick to the original spec unless you're deliberately changing the setup), then clean the faces. This is an intermediate-level job, a classic piece of scooter maintenance, manageable with some method and the right tools (particularly for holding the variator while loosening its nut). Warning: never compress the centrifugal clutch spring (a genuinely dangerous component) during this job -- you're only working on the variator. Risk level: moderate. Cost-wise: a set of rollers runs roughly 10 to 30 euros. While it's open, take the chance to check the belt. This tool helps you understand what's going on -- it doesn't replace a certified mechanic.