You could put an ad in the classifieds here or maybe over at triumph675.net. Or maybe an ad on Craigslist. Beats me what they are worth on the open market. If they are brand new, I'm guessing $250 or so, since whoever buys them will not pay full price and you can get a set of new tires for $300 if you look hard enough and don't need the latest super sticky tires. Just a guess, though.