We've taken delivery of the three Madone 5.2 bikes. Three? Well, one of the main selling points of the Madone used to be that the comfort levels were such that you didn't need a sportive version. Nowadays it's all about choice though, and the 5.2 comes in Pro, Performance and WSD geometries so you can pick the best one for you.

The differences are fairly minimal, but noticeable when the bikes are side by side. We've created this handy – or confusing, possibly – montage of the Pro and Performance models side by side. You can see that the Performance frame (the white one) has a longer headtube (30mm longer) and shorter stem, so the position is more upright. The back end of the bike is exactly the same. Out test bikes had the spacers arranged differently at the front so the positional change is exaggerated a bit, but it is there. We didn't put the WSD in the pic too as it was a 54cm, not a 56, so it didn't really work...

The 2009 bike doesn't share much other than its name with the Madones of old. This is a new design that's got a couple of interesting features. Trek have opted for an asymmetric headset, something we're seeing on many big name bikes this year. the 1.5" lower race allows a larger, and stiffer, steerer and crown, and Trek claim it also reduces weight by 70g.

Another interesting area is the seat tube/seatpost junction. Here Trek have pretty much turned convention on its head: you get a seatpost that fits like a sleeve over an extended seat tube. The clamp is on the seat post, and there are two lengths to choose from giving an adjustment range similar to a standard post. If you think it looks odd, then so did we – what's the thinking behind it?

Well, Trek say that by designing the system this way the high stress area is relocated to a point above the tube junction where the frame can be better designed to cope, and with no seat clamp or seat post the top tube/seat tube junction can be tuned to give a better ride. Because it only needs 30mm of overlap, rather than the more usual 80mm, it's lighter too. Anyway, better designed or not we were specifically instructed on the right amount of tightening for those bolts...

The bottom bracket is unusual too. instead of adhering to the standard 68mm width, Trek have extended the bottom bracket to 90mm and developed a line of internally fitted bearing sets to fit most cranksets. Doing this allows them to make the down tube and chainstay bridge wider and increase stiffness in this important area. Oh, and it's lighter too. Of course.

Anything else? Well, the usual 'it's so laterally stiff yet vertically compliant' line, asymmetric chainstays, a replaceable gear hanger at last, better rear brake cable routing, some unusual tyres that are red on one side and black on the other, and co-moulded dropouts in the fork that are added in the moulding process to improve alignment.

Needless to say, we'll be getting some miles in on all three bikes in the next few weeks to give you our impressions of the different models.