There’s light, and then there’s are you kidding me? That thing is actually rideable? Liberty Bike’s newest creation certainly falls into that latter category with a complete road bike with pedals that tips the scales just South of 9 pounds! Not quite as light as the 6lb road bike we featured a few years ago, but taking the wow factor up a notch is that this bike is built with an 11 speed Dura Ace Di2 drivetrain. Well, at least part of a Di2 drivetrain, meaning the shifters (modified) and the derailleurs. Mael from Liberty Bikes says that he worked with a friend and customer to build what they think is the first Sub-4 Di2 bike in the world (sub 4 kg). While they wanted it to be sub 4, they also wanted it to be safe meaning it could be ridden like a regular bike.

Is it possible to build a bike under 9 pounds that can be ridden like normal? Check out the details after the break! Updated with full specs and details on those shifters!

At the heart of this anti gravity machine is an AX Lightness Alpha frame, which from the looks of it is not a small frame either. The fork is a THM Scapula F with a built in front brake, while an AX Lightness Fibula brake is on the rear.

Using Extralite Ultra Hubs laced to AX Lightness rims, the wheelset for this beautiful machine weighs a staggering 698g for the pair. Carbon chainrings on an AX Lightness crank mate with an extremely light 11-28 cassette for useable gearing for such a light bike.

We’ll have to get more detail from Mael as to what’s going on with the lever, but it looks like the stock rubber hoods have been ditched in favor of a carbon wrap. The Schmolke Carbon bar is wrapped very sparingly with bar tape, extending just past the hoods in either direction.

Update – Just heard from Maël on the shifters, and there’s a lot more going on than we thought. First, the mounting screw on the collar was changed to aluminum. Maël says he didn’t want to go with a carbon collar for safety reasons. The stock hoods are gone and have been replaced with vinyl that has been glued on though it is still able to be removed. Total weight saved? 3g between the two levers. Finally, what Maël rightly calls the hardest job was he somehow managed to remove the stock electronics from the shifters and replaced them with the guts from the TT shifters! He says the system is bigger, but lighter. Wow.

Finally, a very light one piece seat/seatpost provide a place to sit.

There it is – sort of a strange way to weigh a bike, but it works. 3985g, or 8.78542 lbs impressive in metric or imperial. We’re told that it may even get lighter soon as they are working with Cola Wheat and FastDad on a new derailleur!