We've still got a bunch of bikes to tell you about from Interbike's Dirt Demo - 2007 tackle that we haven't ridden enough to call "tested" but can present some brief first impressions of. GT's I-Drive Pro continues the "like an existing bike but in carbon" trend (see also: Giant Anthem Advanced, Cannondale Rush Carbon), being an evolved version of the company's 100mm travel I-Drive 4 platform.

The back end of the I-Drive Pro is the same slimline aluminium as the all-metal bikes. But it's attached to a chunky carbon front end. It's a fairly straightforward shape, with plenty of volume for stiffness and the merest hint of curves. Cable routing is internal, and we particularly like the subtle reinterpretation of GT's trademark pierced seat tube design.

Between the two bits is the I-Drive mechanism, featuring a pivoting bottom bracket that swings back and forth to minimise pedal feedback. We know riders who've tried, but just don't get on with mobile bottom brackets, but we don't find it particularly objectionable - certainly less so than the pedals kicking back at you over bumps.

The Fox RP23 shock is a particularly dinky one, and you do get the occasional feeling that it's having to work quite hard to keep up. Most of the time it's perfectly happy, though. You can coax a bit of give out of the slimline back end, but the chassis as a whole feels pretty stout thanks to the carbon bigness up front. The Pro didn't instantly blow us away like the Anthem Advanced did, but we wouldn't read too much into that - remember, these are only brief rides. We'll try and get a full test soon...