Okay so what makes a scooter a ‘maxi’?
Wheel size? Wheel base? Scooter weight? Engine size?
I know it might be a silly question but hey whats the answer?

i'd say engine size...

Big bodywork coupled with decent underseat storage.

Engine size. They began being called maxis when the 250s came out.

To me it's size as you did get a 125cc X9.

mansize!!!!!

It's a multitude of combinations that determine.
I've always associated it basically with anything over 125cc but those few scooters which have a 125 in exactly the same size frame as the larger models, such as the X9, also get included.
Scooters like the Runners up to 200cc and such, are not Maxi's because they are 50cc sports moped frames with bigger engines shoehorned in. They do not have the physical size despite the over 125cc engines.
I also don't classify Vespa style scooters as maxis because they have their own unique category already in 'traditional' or 'classic'.
The large wheeled Scarabeo type are another oddity in that they can be 500cc, but yet are smaller, lighter and lack the road presence of say a Burger 400. They don't quite fill the job description for a Maxi though but they are more than a moped and you couldn't call them 'sports' from a visual perspective so I don't know what they are.

I suppose that means a Maxi Scooter is one that isn't just a moped or sports scooter with a bigger engine, nor is it any sort of derivative of a traditional design Vespa or Honda Cub. It therefore has to be an original design in it's own right.

TmaX9 wrote: The large wheeled Scarabeo type are another oddity in that they can be 500cc, but yet are smaller, lighter and lack the road presence of say a Burger 400. They don't quite fill the job description for a Maxi though but they are more than a moped and you couldn't call them 'sports' from a visual perspective so I don't know what they are.

I usually think of those as "step-throughs" a la honda C90. To me a maxi is determined by it's physical size i.e burgman, X9/X8/Xevo they also usually have better weather protection, bigger wheels & more storage.

Arse size.

People who's bottoms are "maxi" cant ride a smaller scooter, and so need a "maxi" scooter to accommodate their girth.

I would say that if it looks like a maxi, then it is a maxi....