Modern Vespa

So today I did my 6000 mile service. When reinstalling the variator I noticed in the Piaggio parts manual that there is no washer between the plates and three on the outside, on my machine there is a washer between the drive plates, and two on the outside. Also should there be a washer between the clutch/driven assembly and the inner case? I am new to THIS machine but not to motorcycle construction and maintenance. The lack of information from the manufacturer is frustrating. One more question then I will depart, This machine has a little less than 6k miles and I see that the drive belt has been riding on the bottom and on one of the bosses at the the back of the case...too loose? I read where someone else had that problem and had photo documentation. So whats up with that issue? Any info would be most welcome.

Check the Wiki page on MV. Might be a manual you can download. Or, see if Robot has a video servicing the MP3. Good luck.

I have both the factory workshop manual and parts manual. maybe 2021 was different?

Do NOT ever believe the parts manual for the correct order of assembling parts. They show the inner washer on the outside because if they tried to show it on the inside the driving pulley would either mask it, or the diagram would have to be enlarged.

So yes, there should be one washer inside , and two outside.

Some of us add an extra 1mm washer on the inside to enhance off-the-line acceleration, a.k.a. a 'Fuzzy' washer, after the member who brought it to our attention.