Yeti's AS-R is a well-regarded XC bike, but for 2008 the company has stepped it up by releasing a carbon fibre version, the AS-Rc. The general layout and geometry is the same, the 100mm (3.9in) of rear travel is the same but the construction is packed with eye-catching features.

This certainly isn't just the same bike with a carbon front end. As well as the front triangle, the AS-Rc sports carbon seatstays (complete with slimmed-down bit to permit a hint of flex to allow for the different radii of the swingarm and swing link. Probably the most obvious feature, though, is the integrated seat post. It's an idea that's becoming increasingly popular on the road, and a few MTBs have followed suit. Yeti's implementation, though, seems particularly neat.

The "post" is an elliptical/aero section, which you cut to length and then rely on the choice of seat clamp lengths to get the position spot on. The clamps will also be carbon in production. If you don't like the idea of an integrated post, Yeti will be producing an adaptor so you can just cut the tower off at normal seat clamp height and then run a 27.2mm conventional post.

There's another interesting feature at the bottom bracket. Rather than fit a threaded sleeve to allow a bottom bracket to be fitted, Yeti has extended the BB shell to 90mm wide and oversized it so that the BB bearings can simply be pushed straight into the shell. This also lets Yeti use bigger frame tubes.

Out on the trail it's an impressive bit of kit. Claimed frame weight is 4.5lb - the not-very-adventurously specced demo bike came in at around 24lb complete. The most noticeable characteristic of the bike is the stiffness of the front end. It feels rock solid, exhibiting no flex or twist and contributing to a fine point-and-shoot attitude.

While the benefits of the integrated seat post are debatable, the AS-Rc certainly looks the part. We're particularly pleased to see another subscriber to the "painted carbon fibre" school of thought - there's far too much raw weave on display these days...