The World's Lightest Road Bike
© Emir Ibrahimpasic

This bicycle is the lightest road bike ever built

Weighing just 2.7kg find out how this bike got turned into a lean, mean climbing machine.
Written by Rajiv Desai
5 min readPublished on
A side view of the world's lightest road bike
The World's Lightest Road Bike in all its glory
A road bike that weighs light doesn't automatically make you go faster, but it can certainly help with those power-to-weight ratios, whether climbing up in the mountains, competing in a sportive or going on your daily commute.
Buliding a light bike can be fun but also very expensive. There are weight weenies out there however whose sole aim is to build the lightest bike possible.
The lightest road bike ever built is a custom-made concoction that was originally the creation of one person, Gunter Mai. This same bike has since been rebuilt to be even lighter by Fairwheel Bikes, a bike shop in Tucson, Arizona. We take a look at the story of this bike and how it came to be the lightest road bike ever made.
An angled profile view of the World's Lightest BIke
Fairwheel World's Lightest Road Bike
The world's lightest bike essentially has no name. It was made up of custom-made parts that were specifically designed for the build.
When Gunter Mai built the original bike in 2008 it weighed just over 3kg. Gunter eventually got the weight down to 2.8kg before dismantling everything and selling on various parts of it to other weight-obsessed fanatics in 2010.
It just so happened that the majority of the bike, including the original custom-built frame, was sold on to someone who worked at Fairwheel Bikes, a bike shop that has a big reputation in the weenie bike world for making light custom bikes and building one-off projects.
Before Gunter's bike came along, Fairwheel had held the previous record for the World's lightest bike with their M2Racer Light Bike.
A close up of the handlebars and saddle on the world's lightest bike
Elegance defined
After nearly a year sourcing missing and new parts, Fairwheel's build, featuring Gunter's original Spin frame, came in at 2.7kg. Finished off with minimalist black decals, Fairwheel's aim was to produce a bike that could be used as a working hill-climb racer.
“We of course had already seen the bike and had our own ideas on ways to shave some of the weight from it. We felt it was a shame that he (Gunter) came so close to going below six pounds (2.72kg) but didn't quite push it there, missing it by only a few grams,” said Fairwheel Bikes' Jason Woznick.
A close up of the frame on the world's lightest bike
Carbon custom frame from Spin bikes

Frame and fork

The carbon frame is from German company Spin and was built by frame builder Marc Siebert. It tipped the scales at an incredible 643.9g. This was the frame used on Gunter's original bike.
Like the frame, the carbon fork is the original fork too and is a one-off custom hand-made fork by German company THM. The weight of the fork is 185.9g.
A close up of the gear shifters on the World's Lightest Bike
Lever switch gears

The cockpit

The handlebar, stem, brake levers, brake housing, and bar tape total to just 264.6g. The carbon handlebars were made by Schmolke on a NoRa stem, while interestingly the brake levers were built from what used to be Campagnolo Ergo shifters. The headset went to titanium bearings from what existed on Gunter's bike.
Schmolke also provided the seatpost, which is paired with a Tune Speedneedle saddle. The gear shifters are old-style down tube efforts (lighter) but are made from carbon fibre by BTP. Always a classy look.
An side on profile view of the World's Lightest BIke
Fairwheel Lightest World Bike side on profile
A close up of the brakes on the World's lightest bike
Ax Orion brakes


This is where Fairwheel were able to make the biggest weight savings on Gunter's bike. Gunter's bike had featured Lew wheels that weighed 709.6g but Jason and his team replaced them with their own custom wheel build that featured prototype Ax Lightness rims, a Dash prototype hub, Pillar titanium spokes and Tufo custom tyres. This total wheelset came in at 583g.
Fairwheel added AX Lightness Orion brakes with BTP race pads to the bike, which actually added some weight to the build. The brakes came in at 103.5g. Gunter's previous brakes weighed 71.6g.
A close-up of the bottom bracket on the World's Lightest Bike
Bottom bracket
A close up of the chainring on the World's Lightest Bike
The drive train

The drivetrain

Fairwheel changed the cranks from Gunter's THM Clavicula to a Myth prototype from the Netherlands. The weight on the prototype was 281.4g compared to the 298g of the THM crankset.
Other changes in the drivetrain saw a full ceramic bottom bracket used and new carbon fibre chairings made by Fibre-Lyte added. The chain was switched to a titanium chain made by Taiwanese company YBN. Pedals were switched to a custom-made pair by Aerolite. They were the same pedals that Gunter had on the bike, but just a slightly lighter again version.
Fairwheel added a SRAM Red rear derailleur to the bike. This was heavier than the custom Huret/BTP rear derailleur Gunter had on the bike while the front derailleur is a Campagnolo Record.
A close up of the pedals on the World's Lightest Bike
Pedals as simple as

The future

Jason of Fairwheel explains that the bike went through one more build before it was dismantled and various parts were sold on. LIke before, this build was aimed at making the bike the perfect hill climber. This pushed the weight of the bike up about a quarter of a pound, but it was still lighter than Gunter's version.
Materials and manufacturing processes have moved on somewhat from 2010 and a lighter bike than 2.7kg is within the realms of possibility. Jason agrees that getting a bike even lighter wouldn't be a problem, but ultimately it isn't a project for them.
I decided in the end though that while I have a sub-6lb bike on paper I wouldn't actually build it at this time. Seems just knowing I can is enough for me at this time
Jason Woznick

As a comparison

The world's lightest production road bike is the AX Lightness VIAL Evo Ultrawhich comes in at a claimed 4.4kg for the total bike. AX components actually feature on the lightest custom build, as we mentioned above. AX Lightness has its own frame (weighed at 660g), carbon brake calipers, saddle, seat post and U24T wheels on the VIAL Evo Ultra. The drivetrain features Praxis chainrings and THM-Carbones cranks. The price of the bike is a cool €15,000 (~US$15,800).
An side on profile view of the AX Lightness Vial evo Ultra
The AX Lightness Vial evo Ultra