Unfortunately, this is a common problem with many of today's more exotic frame styles. Last year I bought a slightly used Trek MountainTrack 220 for my daughter, and she was quite dismayed to find that it did not have screw posts like her old Giant bike had. I showed her both in a bike shop and on-line several of the possible solutions, including behind the seat, and handlebar mounted bottle brackets. Despite that fact that the bottle could get dirty, she wanted a cage under the downtube.
I know that I will probably get some flack from some about structural integrity, but here goes. I used a common aircraft modifiers solution to add threaded posts to the underside of the down tube - a product called rivnuts. It is a cross between a pop rivet and a nut. Two carefully drilled 1/4" holes, $1 in parts from the local fastener supply house (plus a modified screw to adapt my Sears pop rivet gun for setting the threaded insert), and she had a cage mount location.
Steve
Last edited by Fibber; 07-18-06 at 08:55 PM.