I have an early 90's Klein Quantum Pro with an integrated stem, Dura-ace, and I love this bike. However, the stem is a 90 and I'd like an 80 cm. I read somewhere that the stem can be replaced with a threadless stem, but my LBM asked me to find out about converting so as to use a regular stem. Any ideas on conversion or where I might look to find the Klein intregrated stem/headpiece in an 80 that was only made for a year or two? Thanks. I'm 1 hour east of San Francisco. There is no Klein website anymore so no instruction manuals available.