Pro bike: Hannah Barnes’ WyndyMilla Bog Warrior 29er

Handmade carbon XC race frame with RockShox and USE goodies

Many pro bikes are based around production models you can buy. However, this WyndyMilla carbon 29er is one of their custom models – only their second mountain bike, the Bog Warrior was built specifically for cross-country team rider Hannah Barnes. You can’t pick it off the shelf but you can go through the bike fit process and get something similar.


WyndyMilla are better known for custom-fitted road bikes created around the needs of the customer, so when Hannah needed a mountain bike they were already in a great position to start designing one for her. 

“Before we started working on Hannah’s XC race bike we had already spent time with her designing a custom geometry for her road race bike,” WyndyMilla designer David Barnes told BikeRadar. “That gave us a really good insight into her pedalling dynamics and the saddle position that we’d need, and it’s great for an athlete to be able to have both race bikes matched up in that respect. 

“The challenge with designing frame geometries for mountain bikes is that the way the bike behaves is incredibly dynamic,” he continued. “You need to come at it from a different perspective to road fitting but essentially the aims are the same. 

“When a bike fits properly, the rider’s weight is supported and distributed correctly across the bike, which has a huge benefit for the balance and handling of the bike. Discussing the ride qualities and handling feel that the rider is familiar with and wants is a much bigger part of designing an XC geometry than it is a road geometry.”

Once the basics were sorted, David and Hannah were able to take inspiration from her previous XC race bike and adjust the geometry to give a more balanced ride, and to work well with the 100mm RockShox SID 29er fork.

An hourglass head tube, internal cable routing and a beautiful custom paintjob:
Oli Woodman/Future Publishing

An hourglass head tube, internal cable routing and custom paintjob

Hannah’s small size made designing the 29er more challenging, as smaller riders tend to require a shorter reach and lower bar. “We’ve had to use a different seat tube shape to allow for the right length chainstay while giving mud space and quite a short head tube,” David explained. “Our unique manufacturing process makes all of that possible and helps us keep our geometries bang up to date.”

The geometry of the frame seems to work, with Hannah saying: “The bike handled really well through the tight twisty parts of the [race] course. Most reports on other 29er bikes say that they don’t handle as well through technical sections but I felt I could chuck it into the corners no problem.”

David said the ability to produce fully custom frame geometries is quite rare these days: “The tubeset and materials are all entirely separate from our road frames. Essentially, the ride is a little stiffer and harder compared to the road frames, as the ride quality is a lot more affected by the tyres and suspension. As for exact blends, we have to keep some things to ourselves!

“The manufacturing process is very different to most bikes out there. Each frame is completely handmade in Italy and built in the Surrey hills; we’re not tied into monocoque moulds so we can change any detail for any customer. The result is a frame that is 100 percent designed around its intended use and user.”

Carbon brake mounts hold the brakes on the chainstays:
Oli Woodman/Future Publishing

Carbon brake mounts

WyndyMilla have integrated layers of Kevlar weave onto vulnerable areas of the bike, such as the down tube and chainstays. “The extra weave not only improves impact resistance but means that if the frame were to fail it would do so in a much more controlled manner,” said David.  

WyndyMilla have built the bike with relatively standard kit, using Shimano’s XT groupset with XTR brakes, USE wheels and finishing kit and a SID Solo Air fork. 

Of the wheels, Hannah explained “they have aerospace nano technology, which means they have a really nice finish and the rim is smooth so displaces mud and water efficiently so you can travel through the mud faster”. David’s highlight is the paintjob, which is fully custom, hand sprayed and with matching fork lowers.

WyndyMilla are able to make the hardtail frame in full custom geometry with 26, 27.5 or 29in wheels, as well as whatever headset and bottom bracket standard the customer wants. The company are also working on a full suspension frame, but want to wait until they’ve got it exactly right before releasing it to the public.

Complete bike specification

  • Frame: WyndyMilla Bog Warrior 29
  • Fork: RockShox Sid 29 Solo Air
  • Headset: FSA
  • Stem: USE
  • Handlebar: USE Carbon
  • Tape/grips: Lizard Skins lock-on
  • Front brake: Shimano XTR 160
  • Rear brake: Shimano XTR 160
  • Brake levers: Shimano XTR
  • Front derailleur: Shimano XT
  • Rear derailleur: Shimano XT
  • Shift levers: Shimano XT
  • Cassette: Shimano XT
  • Chain: Shimano XT
  • Crankset: Shimano XT Double
  • Bottom bracket: Shimano XT
  • Rims:  USE Carbon
  • Front hub: USE
  • Rear hub: USE
  • Saddle: Fizik Arione Donna
  • Seatpost: USE
  • Bottle cages: USE

Critical measurements

  • Saddle height, from BB (c-t): 696mm
  • Seat tube length, c-c: 420mm
  • Tip of saddle nose to c of bars: 523mm
  • Top tube length: 578mm
  • Total bicycle weight: 10.02kg (22.1lb)