Modern Vespa

I want to purchase a new SI 20/20 from SIP. What is the right stuff in terms of gasket for this? SIP says SIP-TIP: Always order the matching air filter at the same time. The carburettor seal, carburettor gasket and SI jetting kit (e.g. #40260000) are all recommended.

Will this new carb be compatible with my old air filter from a SI20/17?

Nope, it wont be compatible, its the same type of air filter but on the 20/17 its called a 'short type' filter, you need the long type.

You need this 20.20 long type
https://www.sip-scootershop.com/en/product/air-filter-si-20-20_11312500?cr=3a6304bb-cc81-4ed5-9f63-1ff45fe1abfa&gad=1&gclid=Cj0KCQjwwvilBhCFARIsADvYi7LW8t4_YWPbGPFJr3wqQva16r8jOoeEPmVLqMn_IQs5mYw1btHkBTkaAiJbEALw_wcB

Because you already have this 20/17 short type
https://www.sip-scootershop.com/en/product/air-filter-si-2015-2017_40255000?cr=3a6304bb-cc81-4ed5-9f63-1ff45fe1abfa&gad=1&gclid=Cj0KCQjwwvilBhCFARIsADvYi7JYYLcSwZh3gsv3Enh7XcxT6xhz1RSd-CNKHy_ljjyjzFuVaZUg4_4aAhSREALw_wcB

The two bolts that secure it, do I need different bolts?

No they'll work as well. The old 20.17 filter won't sit right on the 20.20 carb due to the jets sitting proud of the carb body on the 20.20

My 62 Allstate VNB should have a 20.17 but the PO put in a 20.20 and tried to reuse the old filter. I swapped in the one from my 24.24 until I got a new filter. The 24.24 fits as well.

No they'll work as well.

So silver clasp vs black and longer exhaust tip. Not sure how to make the decision. It's an aesthetic thing.

Just avoid that crap filter with blue mesh. It is too restrictive. Go for original one.

Ok thanks. 20/20 and 24/24 fit same air filter?

I think yes. I use my old original filter from SI 20/20 on SI 24/24 without any problems.

Yes 20 to 26 si uses same filter. I've had Filters come in three colours over the years , green, blue, white and a beige. Can't say I've noticed any difference in any of them but take note if folk say the blue ones are pants then they are likely pants . The last filter than turned up was from beedspeed and this was an official piaggio one in white .

some of the 20/20 filters are 2nd market or "Stella" style with the almost gauze type of material for that extra off road protection.

I've got two blue ones sitting here on the bench with some stockers and they appear identical for all intensive porpoises.

so not all blue filters, I guess?

I'm honestly searching the FMP video about blue mesh filter for an hour but can't find it now.
Only found about it in description for this video: