So, I bought a Trek custom tandem frame from Craigslist a while back. My wife and I have a Cannondale road tandem but it never fit correctly (Ebay purchase) and we wanted to do some of the longer group rides together. The Trek frame had never been built up - the story was that Trek too so long to deliver the frame - and I got it for $300. Over the course of several months, I've built up the frame using parts from EBay with cranks, wheels and fork coming from Precision and Tandems East. Our first ride on it was two weeks ago at the Grizzly Peak Century.
Now, I'm not normally a huge fan of flames and I agree that Trek frames are not the boutique-quality frames that we all know and love... But I must tell you, flames go a long way.
Here are some comments on the build:
1. I don't know how much it weighs.
2. Wound Up fork, 203 mm mechanical brakes front and back.
3. No matter how you order the four words "carbon", "tandem", "disc", and "fork", it will mean a lot of money.
4. The back dropout spacing is 135 mm, which is the only thing custom I can find on the frame. Otherwise, it looks like a Trek T2000. The spacing led to White Industries hubs with Velocity Fusion rims.
5. I bought the two sets of disc brakes so I could get 203 mm discs with the road levers. Before I sell the remaining set of 165 mm BB7's with mountain levers, I'm considering going to the 165 mm discs. I know that heat dissipation and stopping power will be better with 203's, but we're a 300 lb team and would like to take the weight savings, even though it isn't huge. I'm thinking that I'm going to try it and I'll let you know how it goes.