Modern Vespa

Has anyone ever used a 12" wheel for vintage Vespa?
I saw Indonesian scooters using 12" wheel on their P-series. Looks cool, I wonder how that would affect the top speed and long riding experience.

Also, there is a manufacture called Scarletracing that makes 12" rims which using the 10" drum brake as the adaptor.

Each to their own, but personally I find them awful looking on older Vespas…

I think this is what they look like on 12's

Rollin on 40s.

12"s are good for long, straight, fast riding. For everything else, they kindve suck. They make the bike way less nimble.

You're better off spending the cash on better shocks and mounts if you want performance/handling. If you want them for looks, then you do you, I guess.

I have some from SIP that I tried it a few years ago. They're on the shelf now.

And it will ride like a bicycle, or maybe a Honda Cub.

Still using standard shocks and never used a fancy one because I think these are enough. Anyway, what benefits of better shocks can give besides adjustable?

yes it looks bad on non P series.. I saw it once from K.access scootershop

Smoother ride on bumps/rough/broken surfaces, better connection to the road, more stability in turns, so you can lean in further. Much less bouncy overall, too.

I kinda like eight inch wheels on some Indo Ps better than these oversized twelve inch examples, but both look rather odd to me compared to proper tens.

I agree with all of the above and would like to add that don't remember that bigger wheels is heavier and you also need really strong engine or change primary at least. With 12" you will meet big problems with mount/unmount of wheels.

In the past I had P with 110/70-11. I changed it to 110/80-10 because there is lot of bad roads and scoot was very uncomfortable. In both cases I have some problems with mount/unmount rear wheel.
I really like how scoot feels and looks on 11" but reality dictate other - first of all I need comfy and reliable machine on any roads.

The larger tire radius also has a negative effect on the front brakes.

Low profile tires can help and a larger rim does allow for a larger disk. Stock disk is 200mm, 11in rim allows for a 220mm, 12in rim allows for a 240mm. But the larger disk also adds more gryo effect and impacts how quick the bike turns in to corners.

Hence why 8" is far more enjoyable to ride!

Yep. I've been rolling on my VBB a lot lately and enjoying the heck out of it, even on Nashville's craptastic roads.

Cratered roads and eight inch is the way to go. You get to ride down into and up out of potholes. Chico is a mess road wise.