Dear Tom, three quick remarks about your amazing find. The letters on the bits don´t read "Ex-Bee-three", by the way, but "Kh-V-Z", for Kharkov cycle works. Sheer coincidence you can imitate them in Latin script.
One, the year usually is on the r/h side dropout. The frame # usually starts with two figures separated from the rest of the number by some sort of angle, the Cyrillic letter "g", for "god", year. So if it says "84 angle" then that is 1984, for instance.
Two, your blue bike must be a model 155-411 "Start-Chausee", because "CTAPT" means "start" in English. Same coincidence.
Three, the English "Made in USSR" does not imply that your cycle was made for export as all Kharkov-built bikes I´ve seen had the English version. I have had several straight from as well as in the USSR who displayed the same sticker (as do my Perm built roadsters and folders).
Regards,
Toni.
P.S.: In the case of a sudden disruption of an e-mail conversation with me, please assume that I have given up the medium and contact me in a more traditional way. I am in the trial phase of a last ditch system after some others could not stand my constant abusing them.