Modern Vespa

So, last year I gave up on the brakes on my BV before winter, with air in the lines. I'm going after them again, but now seems that nothing is moving. Brake lever squeeze isn't pushing anything, (possibly because of the air?)' I'd wanted to try to push fluid from the caliper, but a good amount of pressure doesn't move anything, (though it does make a nice mess if the line comes off ) and suction just seems to pull air past the threads. So I'm not getting anywhere. My worst case scenario is hauling it an hour down the road to a dealer, but I'm not sure I'm beat...quite. Is there something I might be overlooking?

Usually that sort of thing indicates a seized piston(s). While you didn't mention either way, I'm assuming that's already been ruled out?

No, didn't think of that. It makes some sense, little that I know. Not sure how we go down that rabbit hole.....but worth investigating.

well if you're flushing, then pulling the calipers off won't be the worst thing ever. if anything it allows the lines to drain so there's just new fluid in when you eventually bleed lol.

maybe get a c-clamp on the piston before you remove the caliper from the line just to see if it goes inward at least.

but it may just be worth the mental insurance to yoink the calipers, get the pistons out and install new seals. might find an easter egg

I had a seized caliper on my BV. The only way I could bleed it after replacing the caliper was to wedge shims in the brake and raise it up high. Still took a while to bleed

Sorted. PM on the way...

Just in case someone stumbles on this in the future:

Embarrassing, but lack of fluid movement turned out to be stupidly confusing brake levers.

Eventually sorted it out, took way too long, but persistence paid off. Did a bit of everything, from pushing fluid from below, traditional lever pumping, Mitey Vac-but can't identify once clear win. Just seemed to get resistance, tried a bit more, but clamping lever overnight took it to a satisfactory level. It's still a great mystery....

More information on raising the caliper to get air out of the lines please! What were the steps?

I took my BV350 to an outstanding independent shop to bleed the brakes (and lots of other things). The back brake no longer works. The mechanic said that was the first time this has ever happened to him. He tried twenty times to bleed out the air, but no joy. He stated that he believes there is air in ABS unit and only a dealer has the tool to actuate the ABS system while bleeding the brakes. I've seen the tool on sale for $614 on Ebay, but that is too much to pay for a tool I might only use once and won't come with the data updates that dealers get each year.

My local dealers are horrible, so I plan to drive down to San Diego to get this fixed. ... unless I can do it myself.

Sorry, I missed this. Maybe you go this sorted already, but what it takes is to remove the two mounting bolts for the caliper, wedge a piece of wood between the pads (and try to be sure it won't fall out....it doesn't help the process to find it on the ground ), remove the mounting bolt holding it to the exhaust support and raise it to about seat level.

I wasn't sure if orientation of the caliper mattered, but I did rotate it a bit a couple of times when drawing fluid out.

Not sure whether that was key to my success, as I was trying so many approaches it just seemed to work at some point. I swear at one point I had no idea what I was doing anymore, nothing seemed to work, and just at minus one hour or so (from loss of sanity), it did. Persistence seems to be a major factor.
But assuming you're less German than me (ask my wife about stubbornness ), a good dealer may be worth the trip.