I have the opportunity to buy a new '06 Jamis Xenith Pro frameset for a few hundred dollars. I'm very tempted. I would buy the frame and build it up (my first build-up). I currently ride a LeMond '04 Buenos Aires (CF and steel mix), and want to try a full-carbon bike.

I have a question regarding the carbon fiber in the '06 vs. the '07 frame for the Xenith line. The '06 frame material is described on the Jamis site as: "Full carbon fiber composite frame including lugs, sloping top tube design, monostay seatstays, replaceable derailleur hanger."

Jamis has changed it carbon fiber for its '07 line, now described as: "Monocoque construction utilizing two diferent carbon fiber types (DYAD lay-up) for increased stiffness & resilience Tri-Oval differential tubing diameters . . . Asymmetrical muscle-shaped chainstays with driveside chainstay 10% larger than non-driveside chainstay yields 30% more volume & stiffness to offset the high loads of sprinting torque." Bicycling magazine, for one, has raved about the new '07 Xenith Comp.

Can anyone tell me what kind of difference a "monocoque" frame has over one that is lugged? I spoke with my local LBS and the expert there said some CF is too "whippy" in the rear triangle and can also have too much flex at the head tube, adversely affectign the handling. The first question he asked about the frame was whether it was a monocoque frame or not.

Any information would be appreciated. Apparently the '07 Jamis frame is a newer generation CF. Would I still be getting a good deal on the '06 frame, all things considered? Note that my riding style is as an enthusiast, with some racing in duathlons and triathlons (Masters category), but my primary goal is to *enjoy* the riding I do. I'm an older rider, so the higher head tube on the Xenith is appreciated (back and shoulder issues, y'know).