I somehow lost the transmission dust cover on my GTS ages ago. Tried to order the part from my local Vespa (BMW-centric) dealer to no avail. I ordered part number #CM121908-1 from an online vendor according to an online parts diagram. What arrived was part #CM155106. I have heard other dealers complain of Piaggio revising part numbers. The part which arrived also did not fit. The plastic tabs are too small for the holes in the transmission cover.
Several phone calls and e-mails to the customer service phone line revealed I now needed to order three of part #871458 (little rubber grommets which I'm sure will be lost in the future as well).
Piaggio not only changed up the part numbers, but also the part as well. Why can't Piaggio just include them with the obscenely expensive piece of shiny plastic dust cover in the first place. Or at the very least, auto order the stupid grommets when the old part number is entered in the system. And now there's shipping for a second order by no fault of my own. I want to make it clear I'm not complaining about the vendor who was just as screwed as I was.
Piaggio, if you're reading this, you suck big hairy sweaty donkey balls for this stunt.