Finally, trying the tubulars again. Back in 2017, just before my LBS retired, I got a pair of Conti Giro's. Had my old wheels trued, cleaned and mounted the tubs, with Tufo tape. After hanging on the rack, for the winter, I put them on my Concorde, only to discover, the rear had developed a flat spot(over tensioned in one area). So, I hung them back up. Now with 7 bikes and spare wheel sets, it was time to buy an truing stand, rather than paying another LBS $15 a pop to tru my wheels, After 1.5 hrs. playing with that rear wheel, I got the flat spot out. Re-taped the rim, mounted the tub, and added some Stans sealant for good luck. Found a good spare tub, and like the olden days, strapped it under my saddle and away I went. Sixteen, sweet miles and one 40mph down hill run, it was totally , pure fun. Although, 22mm tubs, aired to 120lbs. was a little bone jarring, after todays rain, I'll work on lowering the pressure a little. All my bikes have been converted to 25/28mm tires and found the lower pressures, nice.
And yes, the Conti's do not have a removable valve core. Installed the Stan's at 10 o'clock, inflated the tubs, bounced them around a bit, rechecked the valves for any sticking. Checked again today, nope, no sticking valves and aired up just fine.
Now, if I can find a good air pressure, I'll ride the tubs, the remainder of the season. Was inspired by this thread. KB.