Sonder Vir Fortis Makes days and nights to remember on mud, sand and snow. Rovaniemi 150 Race Winning full carbon fat bike adventurer.
Full carbon fat bike adventurer for snow, mud and sand. Make winter riding days and nights to remember. Full fat and go where no other bike can. Vir Fortis slack geometry makes for a fun characterful trail-friendly ride on wintry days. Float over surfaces on big 4.8” tyres.
Built for exploring and Iditarod capable, Vir Fortis is a Rovaniemi 150 Arctic Winter Race Winner. It isn't your regular faceless hero.
Compatible with 4.8” tyres, Vir Fortis is set up to get you over the most challenging terrain. Vir Fortis might not be the bike you ride everyday, but it will be the bike you want to ride everyday!
Geometry with a trail riding pedigree, Vir Fortis positively encourages you to explore the outer limits of wintry trail and cross country riding. The ultimate expression of this is finding terrain which used to be a no go area for bikes - like snow, mud or sand.
The only thing wider than the grin on your face will be your tyres - and that’s as it should be. Go nice places regular bikes can’t go. Bigger tyres equals bigger adventures.
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.
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 (kg): 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|
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:
Riders between 5ft 2in and 5ft 7in
Riders between 5ft 6in and 5ft 10in
Riders between 5ft 9in and 6ft 2in
|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|
Swapouts and Upgrades
You can interchange Love Mud components on this build at no additional cost. So if you want a different length of stem, a particular saddle or bar then let us know in the notes section in the checkout and we'll get in touch. We also hold big stocks of SRAM, Rockshox, WTB and regular build with Shimano, Hope, Cane Creek. We'll build your Sonder with any part that suits your needs. Give us a call, with the same experienced mechanic helping throughout your build you know who to call if there's anything you want to know.
- Are Sonder available outside the UK?
- What are builds and groupsets?
- When will you get your bike?
- I’m between bike sizes - which size should I choose?
- Common Bike Upgrades: price list
- Try Before You Buy - Sonder Demo and Bike Hire
- Which wheelset for which Sonder Bike?
- How much does international shipping for Sonder Bikes and Love Mud Wheels cost?
- Cycle to Work Schemes
Alpine Bond Warranty
We offer a 10 year guarantee on both our handmade titanium and Reynolds steel frames. Our hand welded 6061-T6 alloy triple butted frames and carbon frames come with a 5 year manufacturing defect warranty. All our bikes are built, checked and signed off by Cytech trained mechanics before being despatched to you in a custom-made bike box.
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