Florence to Tuscany via Vespa

Florence is already in Tuscany (it’s the Seat of Tuscany’s Region in fact).
Assuming you know how to ride a motorcycle or a motoscooter already, a nice drive would be to take the SR222 (Via Chiantigiana) from Viale Europa.
You could do Viale Europa - Greve - Panzano - Castellina - Radda - Volpaia - Lamole di Lamole - Greve and back. Lots of wineries along the way.
I’ve ridden my Vespa in that area tons of times in my youth (I used to live near Viale Europa).
It’s going to take you the best part of a day. Your arse will ache at the end of it.

Pisa is too far by Vespa, and you could do it only in a separate trip. Since you will probably rent a 125cc, the freeway will be forbidden to your Vespa, so you would need to use the Via Pisana, through the towns of the Valdarno Inferiore, where there is also a lot of truck traffic. The scenery is nowhere as great as the Chianti, suggested above.

Last month we drove to lamole/ greve area from
Impruneta and agree that would be a nice area - very scenic. Assuming you would be coming from
Florence to Chianti area.
We experienced a group of tourists on vespas (first time for me seeing this in Tuscany as a popular tourist activity) and if you haven’t done this before just know the road conditions can be a bit stressful if not used to Italian roads (annoyed drivers, very small roads with turns you can’t see around etc) . The drivers were not happy with the low speed of this particular newbie Vespa group (we assumed the rentals only go to a certain max speed) . Anyway just agreeing with Roberto that hopefully you are comfortable on a Vespa and knowledgeable / have had experience with Italian road conditions. You do see motorinos and such on the road but most drivers have had a lifetime of experience on these roads and are very skillful.

hitting a couple vineyards if possible.

We will be driving around that area in October.
If you plan to wine taste on your Vespa day could you let me know the date so we avoid the roads then?