So, I took off for a little ride this morning, and got about two miles before the TPMS Warning illuminated, showing rear pressure down to 29psi. A quick ride back to the apartment allowed me to air it up with a bicycle pump, and I was back to the Triumph Dealership which luckily is open every day. The bad news is they, like most Dealers these days, refuse to repair punctures like the one this ten penny nail inflicted. They didn't have a replacement Pirelli Angel ST in stock, but did agree to match the lowest online price I could find of $130. I guess I can't complain too much as it has been 20+ years and 200,000+ miles since my last flat tire. I will ask for my old tire back to see if it is worth repairing, given it is probably nearly half worn anyway with 4,200 miles on it.