Sonder Vir Fortis GX Eagle

Sonder Vir Fortis GX Eagle

Full carbon fat bike

£2,099.00

When you want to go places a regular skinny bike won’t, go you need a hero. Enter Vir Fortis, a bike made for terrain that may never have been navigated on two wheels, crushing turnips, or for just in case you get snowed in and need to save the neighbourhood.

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All Sonder bikes are built to order and can be customised. Our build time is currently 5 weeks.

You can make your selections on the next page.

Build your bike

Select your size and make any changes you want from the standard build. When you’re done, hit Add to Bag at the bottom of the page

  • Frame

    Size
    Please select your Size

    Configure your Frame

    size

    • Small

    • Medium

    • Large

  • Accessories

    Bottle cages
    No Bottle Cages

    Configure your Accessories

    Bottle cages

    • No Bottle Cages (none)

    • No Bottle Cages
    • Love Mud Sideblade Left Entry / Black

      +£4.99

    • Love Mud Sideblade
      The Sideblade bottle cage not only gives your water bottle a lovely, secure hug, but its side loading system makes it easier to access when you need a drink, making staying hydrated a joy even when you've got a load of frame bags to work around!

      The Side blade is geared at letting you get to your water when you've got a bike packed up with frame bags, this means that it's also ideal for compact and full-sus frames where a standard loading bottle cage system just won't fit, you can choose which side you'd like to access your bottle by with a twist of the cage in the mount before your ride.

      Made of polycarbonate, the Sideblade is also super light and super duper tough - hooray!
    • Love Mud Sideblade Right Entry / Black

      +£4.99

    • Love Mud Sideblade
      The Sideblade bottle cage not only gives your water bottle a lovely, secure hug, but its side loading system makes it easier to access when you need a drink, making staying hydrated a joy even when you've got a load of frame bags to work around!

      The Side blade is geared at letting you get to your water when you've got a bike packed up with frame bags, this means that it's also ideal for compact and full-sus frames where a standard loading bottle cage system just won't fit, you can choose which side you'd like to access your bottle by with a twist of the cage in the mount before your ride.

      Made of polycarbonate, the Sideblade is also super light and super duper tough - hooray!
    • Love Mud Sideblade Pair / Black

      +£8.99

    • Love Mud Sideblade
      The Sideblade bottle cage not only gives your water bottle a lovely, secure hug, but its side loading system makes it easier to access when you need a drink, making staying hydrated a joy even when you've got a load of frame bags to work around!

      The Side blade is geared at letting you get to your water when you've got a bike packed up with frame bags, this means that it's also ideal for compact and full-sus frames where a standard loading bottle cage system just won't fit, you can choose which side you'd like to access your bottle by with a twist of the cage in the mount before your ride.

      Made of polycarbonate, the Sideblade is also super light and super duper tough - hooray!
  • Finishing kit

    Pedals
    No Pedals

    Configure your Finishing kit

    Pedals

    • No Pedals (none)

    • No Pedals
    • Shimano M520 Pedal Black

      +£39.99

    • Shimano M520 Pedal
    • Shimano RS500SL Pedal Black

      +£39.99

    • Shimano RS500SL Pedal
    • Shimano A530 Pedal Black

      +£39.99

    • Shimano A530 Pedal
Initial Price
£2,099.00
Extras
£0.00
Grand Price
£2,099.00
Go to Checkout
Description

Vir Fortis is designed to go anywhere, big tyres and big wheels gives a massive amount of traction.

Vir Fortis is not just strong, it is light too: a medium frame weighing in at just 1550g and letting you float over the wildest trails like a cloud. It looks sharp: cables are routed internally to avoid snagging and keep things clean, and a single mounting point on the downtube gives you the option to add a bottle cage.

With a race-winning pedigree, Vir Fortis inspires you to explore the outer boundaries of the trails. Its slackened off geometry gives a characterful ride and is compatible with tyres up to a chunky 4.8”. It’s carbon frame and fork gives precise handling and trail bike feel.

It has taken on some of the roughest rides in the wildest terrain, and come out on top.

At a glance
  • Fat, light, and comfy for wilderness exploration
  • Frame: Sonder Vir Fortis, high grade T700 carbon
  • Groupset: SRAM GX Eagle / 1 x 12 / 10-50
  • Brakes: SRAM Guide R
  • Fork: Vir Fortis, high grade T700 carbon
  • Seatpost: Love Mud Membar, 31.6 mm
  • Wheelset: Love Mud Hurlyburly
  • Tyres: Vee Rubber Dozer 4.25
Reviews
Geometry and Sizing

Sizing

It is important to get the right size bike, if the bike fits it will be faster, more comfortable and easier to handle. You can also take into consideration the standover height to ensure you pick a bike that will be a good fit. If you measure your inside leg and ensure there is a minimum of an inch from the toptube to your crotch this will give you enough seatpost adjustment to find your optimum saddle height. Generally we recommend: Small Riders between 5ft 2in and 5ft 7in Medium Riders between 5ft 6in and 5ft 10in Large Riders between 5ft 9in and 6ft 2in
Size Small Medium Large
ST - Seat tube 406 457 505
TT - Top tube 580 605 625
HT - Head tube 100 110 130
HA - Head angle 68.5 68.5 68.5
SA - Seat angle 73.5 73 73
CS - Chainstay 445 445 445
BB - BB drop 60 60 60
FO - Fork offset 45 45 45
WB - Wheelbase 1103 1123 1145
SO - Stand over
RE - Reach 406 423 437
SK - Stack 586 595 614
Build Spec
Build Vir Fortis GX Eagle
Frameset
Frame and Fork: Sonder Vir Fortis Frame and Fork
Headset: FSA Orbit C-40-ACB Headset / 7.8mm Spacer
Seat Clamp: Love Mud Gromit / 34.9mm
Group Set
Brake Front: SRAM Guide R / 950mm
Brake Rear: SRAM Guide R / 1800mm
Rotor Front: Avid Centreline Rotor / 180mm
Rotor Rear: Avid Centreline Rotor / 160mm
Rear Mech: SRAM GX Eagle Rear Derailleur / 12 / Long
Rear Shifter: SRAM GX Eagle Trigger Shifter
Chainset: SRAM GX Eagle Fat Crankset / 175mm / 30T
Bottom Bracket: SRAM Bottom Bracket / Fat
Chain: SRAM GX Eagle Chain / 120 Links
Cassette: SRAM XG1275 Eagle Cassette / 12 / 10-50
Finishing Kit
Stem: Love Mud Piskie Stem / 31.8mm / 55mm
Seatpost: Love Mud Membar / 31.6mm / 400mm
Saddle: Love Mud Abode / Black
Tape/Grips: Love Mud Clutch / Black
Handlebar: Love Mud Aspect Riser
Wheelset
Wheels: Love Mud Hurlyburly Wheelset
Front Tyre: Vee Bull Dozer / 26 / 4.25
Rear Tyre: Vee Bull Dozer / 26 / 4.25
Tubes: VEE Inner Tube / 26 / 4.00-4.80
Weight
Frame: S: TBC kg; M: TBC kg; L: TBC kg; XL: TBC kg
Built: S: TBC kg; M: TBC kg; L: TBC kg; XL: TBC kg
Pedals not included with full builds
FAQs
TBC
Frame Spec
Carbon is the most versatile material for building a bike frame, not only can you mold it to look exactly how you want, you can also layer it up differently to affect the ride characteristics. This allows us to build frames that are stiff in the areas they need to be and have the right amount of compliance in others making for an incredibly lively but comfortable ride.
Frame Weight: S: TBC; M: TBC; L: TBC
Fork Weight - uncut: TBC
Toray T700 carbon fibre
Headset: IS42/28.6 | IS52/40
Seat post: 31.6 mm
Seat tube OD: 34.9 mm
100mm BSA BB shell
Features

Hand laid carbon fibre frame and fork

Using Toray’s highest grade of carbon, T700, this frame is manufactured in a clinical environment to the highest standards. The result is an extremely strong, lightweight frame that is a blast to ride! Guaranteed for 5 years

Trail bike inspired geometry

The Vir Fortis take fun to the next level by slackening the bike out a bit, giving it a more relaxed, playful character. With natural air suspension from the enormous tyre volume Vir Fortis is ready to roll over all terrains.

Internally tapered head tube

Who would choose to be a head tube? You might as well step into the ring with Mike Tyson. It is a critical junction point where forces are distributed around the frame and steering precision is won or lost. Vir Fortis uses a fully integrated internal headset and a fork with a tapered carbon steerer tube to make sure you hold your line over broken ground.

Disk brake compatible

​Once rolling you will be surprised by how you can carry your momentum which is why you are going to be thankful for the stopping power of disc brakes. The Vir Fortis carbon frame is fully compatible with disc brakes.

High spec builds

If you’ve a dream build in mind, please get in touch and we’ll do our best to source the parts you want.