Modern Vespa

my x9 manual says like@ 8000 miles, should'nt they last longer?
never had any problems so far and never rode a scoot that had them in need of changing, what will the scooter act like when this happens?

Variator rollers are consumable items. The rollers have had a long and hard life at 8,000 miles of service. Although its possible your scoot seems to be okay, CVT performance has been compromised over the rollers lifetime. Its prudent to replace the rollers. They're inexpensive (around $25 per set), and not hard to replace.

At 6000+ miles one of my GT's rollers had developed a flat spot.

you might be able to get 10~12 out of them but given the risk of damaging the variator components with bad rollers i'd opt for the 8K option or just roll it to 10 and do the belt at the same time....

when the rollers go you get a shuddering at take off and in the lower rpm range.

best,
-greasy

that's freekin' awesome mileage for a roller!
usually you'll see flat spots starting to develope anywhere between 2800~3500.

best,
-greasy

i do alot of highway driving, is threre any difference in roller life from driving alot of stop and go driving?

and: That's exactly what my dealer said was causing my "shudder". That and dust. They cleaned stuff out and said to come back at 6000 for replacement.

It's been working fine since then (though it's only been a week).

Oooookay. This would probably explain why I noticed a shuddering when accelerating from a standstill on my ET4. (It seems to diminish after the scooter is warmed up and on the road for a while, though.) Started about a month or so ago. I have a little over 4,000 miles on it.
Otherwise, everything seems to be working fine.

With the colder weather arriving, this would be a good time to teach myself a bit more about do-it-yourself scooter maintenance.

Is there a blow-by-blow description of how to do replace the rollers anywhere?

the GT200 shop manual gives you the specifications for the min roller diameter. You measure them with calipers and replace if they have reached minimum diameter. I pulled mine at 8,000 miles and they were well within the tolerance level. I drive mostly highway though, with very little stop and go. I plan on replacing them regardless at my next service at 12,000.

That's true, but the problem a lot of folks are seeing at fairly low miles is rollers with flat spots, which cause problems and should be replaced.