Modern Vespa

Greetings, Vespa Nation —
As summer approaches and I prepare to perform the sacred ritual of routine maintenance (fluids, filters, spark plug — the holy trinity), I find myself contemplating going a step further: brake pads.
The rear brake has developed a charming squeal, specifically reserved for those tender moments when I'm creeping into a parking spot. Now, I know what you're thinking — "he probably never uses the rear brake." Correct. And yet, here we are. 6,000 miles in, zero pad replacements, and apparently physics has caught up with me.
For context, I reside in New York City — where the brake is not so much a suggestion as a full-time coping mechanism. I tip my helmet to those of you cruising the Welsh countryside or Queensland's Outback, where I imagine the biggest braking hazard is a wandering sheep. We are not the same.
So here is my question for the esteemed council: do I go back to OEM pads and call it a day, or is this the moment I finally upgrade to ceramic/sintered pads and pretend I know what I'm talking about at the next scooter meetup?

All wisdom gratefully received. Ridicule also accepted if warranted.

If you never used the back brake, they never got bedded in. Take them off, sand the material a bit to take off any glazing and reinstall. I mean, if you are not really planning to use the back brakes, (and I don't know why you won't) then the pad materials shouldn't matter if they're ceramic/sintered pads or made of Swiss cheese. As far as the front pads go, use the best you can afford - that's 80% of your stopping power.

Edam for the rear but Parmesan for the front.

Try sintered on the front and see what you think. Some say it wears the discs out quicker but unless your going into corners like Colin Edwards or Nicky Hayden you probably wont tell that much difference.

I mostly use the back brake for slow control turning to keeps thing shape.

2018 GTS has sintered pads on the front from the factory, Piaggio went sintered with ABS.

You don't need new pads, at 6k factory pads will be barely worn. Rear pads have an anti-squeal shim. Pop the pads out and apply a bit of moly brake grease to back of the pads, should cure it.

not arguing, just asking ...

do you have a reference for that? oem pads are not known for eating the disc but sintered aftermarket are known for eating discs.

the part number for the pads 668021 on an hpe on sip show ferodo printed on them. I did a google and came up with this link https://www.mxonlineaustralia.com.au/ferodo-front-brake-pads-for-vespa-gts-300-super-te which says they are ferodo and _non sintered_

I thought these polyurethane shims would be snake oil, but to my surprise they cured my brake squealing issues completely and immediately. I think Robot recommended them once upon a video.

https://www.amazon.com/dp/B006RA9E90

Not sure grease works the same way...if at all.

Is grease anywhere close to brake pads a good idea?

OFG

?si=3wZ4yagKXR7Hs_jN

Part number changed in 2014, will fit earlier Heng Tong calipers.

https://www.scooterwest.com/oem-sintered-front-brake-pads-gts-300-abs-bv-350-abs-668021-651253.html

Quick internet AI answer:

for anyone else playing along at home and likes cross referencing from parts manuals, I looked up these in the parts manuals for the different years instead of trusting SW's abbreviated listing.

647078 pre abs heng tong pale green paint
https://www.sip-scootershop.com/en/product/brake-pads-piaggio-s51-heng-tong-brake-calliper-front-647078_PI647078

651253 pre abs heng tong black paint
https://www.sip-scootershop.com/en/product/brake-pads-piaggio-s51-heng-tong-brake-calliper-front-left-651253_PI651253

668021 abs ferodo silver
https://www.sip-scootershop.com/en/product/brake-pads-piaggio-s51-668021_PI668021

So looking at the pictures the visible texture of the pads clearly changes from chunky looking with the pre abs heng tong to a fine texture with the ferodo pads with abs in 2014. This is the sorta info I like.