Scooterotica

Sounds like a really good set up. That BGM 177 is a really high rpm quality kit. When combined with a 60mm Mazz crank its going to scream even higher. This is a good thing.

Will never pull a PX200 gearbox, so forget that idea. As it will rev so high it should be fine with the 21/68 and a 36 tooth 4th and still overtake any PX200 on the motorway.

The SI24/24G is a great idea with a high revving motor and a longer duration inlet. Keep all the T5 jetting (120 air, BE4) just up the main jet quite a lot. I would keep the autolube running too. All the seizing problems with SI carbs on tuned motors is that they are difficult to set up correctly but we can talk you through it.

Cheers for the info guys, I now have a basic set up.
The reason I picked the 24g carb is its was designed for a higher revving engine, but I'm really only at the start point and have no experience of vespa carbs.
I'm trying to weigh up the hassle/cost to power benefit of a 60mm crank gives over a standard, I'm not really looking for the fastest scoot on the block, I do want something that will drag me around though.
It's time to get the donor bike so this thread is likely to go quiet for a few months.
Lots of food for thought.