looking to get the lowdown on my bike. please help! i think it is a 1988 or 89 from vintage trek website, not sure.. here are the spec. made in the USA, SN 363513, ovalteck chainring, sakae sx chaincrank, shimano SLR brakes, shimano acera x rear derailer, 18 speed, shimano SIS index system, matrix titan rims with mechelin erilum kavlar reinforced tires, mallard 500 hubs ( made in france ). has a vette seat............ brake pads, tires and handlebar padding are all new... and has had a recent tune-up.. cables run through the chainstay and has a slanted TK emblem on the head tube. seems to me to have components from 88 and 89 maybe a 1988 & 1/2 if possible. either way a nice ride. also ..what may the value be if i wanted to up grade. i have invested 235.00 so far... to much!... ok .. not bad.....what do you think.. thanks