Saturday, February 28, 2026
Big Fat 47K / Half Fat 21K / Fun Fat 10K
American Birkebeiner Trailhead, Cable, WI
The Fat Bike Birkie is North America’s premier on-snow bike event. Riders test their skill and endurance on the professionally groomed American Birkebeiner Ski Trail, with options for every rider’s ability level. Choose from three epic distances: the Big Fat 47km race, the Half Fat 21km race, and the Fun Fat 10km Tour. And the fun doesn’t stop after the finish lines – test equipment at the Birkie Fat Bike Expo and enjoy live music and food at the post-race party!
Fat Bike Birkie was voted the #1 Best Fat Bike Event in the Midwest by readers of The Nxrth.
The Fat Bike Birkie was also rated one of the American’s Top 5 Premier Fat Bike Events by Hycline.
Join us this winter and ride the route that riders can’t stop raving about — the snow-covered, world-famous Birkie Trail.
The Birkie Trail Staff groomers share the goal of providing a firm surface to ride on for the races. However, course conditions and weather can vary widely, from hard packed to soft powder snow. We recommend that participants be prepared to race in any course conditions. Just like in the Birkie Ski race, Fat Bike Birkie participants are free to choose different equipment based on the conditions of the course. Bikes should equipped with at least 3.5 inch wide tires, suitable to course conditions.
Please note, Class 1 fat bike e-bikes are allowed in the Fat Bike Birkie. At this time, e-bike riders will not be eligible for awards or results placement.
| June 10 through November 13 | November 14 through January 15 | January 15 through February 19 | February 20 through Race Day | |
|---|---|---|---|---|
| Big Fat, Half Fat or Fun Fat | $80 | $90 | $100 | $110 |
Registration closes on Saturday, February 28th. Registration for Big Fat after Thursday, February 26th at 7pm will be placed in Gate 4 only.
All Big Fat 47K participants must be at least 16 years of age on race day. All Half Fat 21K and Fun Fat 10K participants must be at least 12 years of age on race day.
Tandems bikes are allowed but will not be eligible for an individual award category. Each tandem rider must register and contact registration@birkie.com to ensure the proper results are shown.
The deadline for requesting a change in race/event distances is Friday, February 27th at 7:00pm CST.
Protect your registration! Get reimbursed up to 100% on your registration if you can’t compete for a number of reasons. Protecht offers refund protection so you can insure your non-refundable registration fee in the case of injury, illness, or other unexpected events. Protecht can be purchased during your initial registration or up to five days after registration is completed.
The Birkie gear bag has large, heavier zippers and plastic clips throughout the bag.
Riders will be assigned to multiple start gates based on the last 3 year’s of Fat Bike Birkie results for all races.
The Big Fat (47K) race will feature 4 start gates. Riders will be placed in one of these gates based on their best finish time from the previous 3 Big Fat or Half Fat (21K) races. Riders without a result in the past 3 Big Fat or Half Fat races will be assigned to Gate 4.
The Half Fat (21K) has just one start time and gate.
| Big Fat Gate | 2025 Big Fat Finish Time | 2024 Big Fat Finish Time | 2023 Big Fat Finish Time |
|---|---|---|---|
| Gate 1 | 1:46:56 to 2:16:52 | 1:46:25 to 2:10:54 | 1:49:57 to 2:06:27 |
| Gate 2 | 2:16:53 to 2:40:24 | 2:10:55 to 2:34:18 | 2:06:28 to 2:31:44 |
| Gate 3 | 2:40:25 to 3:07:08 | 2:34:19 to 3:00:55 | 2:31:45 to 3:06:55 |
| Gate 4 | NEW PARTICIPANTS & PARTICIPANTS WITH NO RESULTS FOR LAST 3 YEARS | NEW PARTICIPANTS & PARTICIPANTS WITH NO RESULTS FOR LAST 3 YEARS | NEW PARTICIPANTS & PARTICIPANTS WITH NO RESULTS FOR LAST 3 YEARS |
| Big Fat Gate | 2025 Half Fat Finish Time | 2024 Half Fat Finish Time | 2023 Half Fat Finish Time |
|---|---|---|---|
| Gate 1 | ACHIEVED WITH BIG FAT RESULTS ONLY | ACHIEVED WITH BIG FAT RESULTS ONLY | ACHIEVED WITH BIG FAT RESULTS ONLY |
| Gate 2 | 0:49:06 to 0:56:28 | 0:38:35 to 0:46:18 | 0:51:35 to 0:59:19 |
| Gate 3 | 0:56:59 to 1:08:44 | 0:46:19 to 0:53:15 | 0:59:20 to 1:11:11 |
| Gate 4 | NEW PARTICIPANTS & PARTICIPANTS WITH NO RESULTS FOR LAST 3 YEARS | NEW PARTICIPANTS & PARTICIPANTS WITH NO RESULTS FOR LAST 3 YEARS | NEW PARTICIPANTS & PARTICIPANTS WITH NO RESULTS FOR LAST 3 YEARS |
All Fat Bike Birkie races start and finish at the American Birkebeiner Trailhead in Cable, WI. Access to the start area is available ONLY from Telemark Road off of WI Highway M. From Cable, WI, Take Highway M traveling East out of Cable for 2 miles. Turn right on Telemark Road.
Follow Telemark Road as it passes the former Telemark Lodge to the designated parking areas. Follow the directions of the parking attendants. The start is accessed via a short pedestrian path.
3:00 pm – 6:00 pm — Derksen Family Great Hall *New time!
7:30 am – 9:30 am — Derksen Family Great Hall
| 1:00 pm – 4:00 pm | Tentative Pre-Ride |
| 3:00 pm – 6:00 pm | Bike Plate Pick-up *New time! |
| 7:30 am – 9:30 am | Bib Pick-up |
| 9:00 am | 47k Big Fat Start |
| 9:10 am | 21k Half Fat Start |
| 9:25 am | 10k Fun Fat Start |
| 11:00 am – 3:30 pm | Post Race Party! |
| 11:00 am | Half Fat Overall Awards |
| 11:30 am | Big Fat Overall Awards |
| 12:00 – 12:30 pm | Age Group Awards |
| 3:00 pm | Finisher Cut-off |
Fat Bike Birkie Expo
The Fat Bike Birkie Expo provides riders with an awesome opportunity to test out top-of-the-line fat bike and outdoor lifestyle gear, chat with industry professionals, and collect event swag.
Big Fat
Half Fat
Fun Fat Tour
The Big Fat 47K course will ride out on the Birkie Skate Trail to the Powerlines, make a quick turn to the left and rejoin the Classic Trail. After riding on the Classic Trail to OO, the course will return on the Birkie Skate Trail to the Powerlines where it will come into the finish.The Half Fat 21K course will ride out the Birkie Skate Trail to the Powerlines to Timber Trail where it will enter the Half Fat only course. The Fun Fat 10K Tour will ride on a mix of Birkie Classic Trail, smaller ski trails, and the Half Fat course before finishing the same way as the Big Fat 47K and Half Fat 21K races
| Big Fat Aid Stations | Distance from the Start (K) | Cut-Off Time |
|---|---|---|
| Timber Trail Southbound | 8 | 10:00 AM |
| Fire Tower Southbound | 14 | 10:40 AM |
| Boedecker Southbound | 19 | 11:15 AM |
| Boedecker Northbound | 29 | 12:30 PM |
| Fire Tower Northbound | 34 | 1:00 PM |
| Timber Trail Northbound | 38 | 1:30 PM |
| Finish | 47 | 3:00 PM |
| Half Fat Aid Stations | Distance from the Start (K) | Cut-Off Time |
| Timber Trail | 8 | 10:30 AM |
| 13K | 13 | 11:15 AM |
| Finish | 21 | 1:30 PM |
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Learn how to refuel with Untapped!
Stay tuned to find out when and where the pre-riding of the course will happen.
Please note that riding bikes on the Birkie Trail during the winter is only allowed on the days designated for the Fat Bike Birkie event. However, winter bike riding can be accessed from many of the trailheads utilizing the Chequamegon Area Mountain Bike Association trail system. Trail conditions can be found on the CAMBA Winter FAT BIKE page.
No special equipment classes will be recognized in the Fat Bike Birkie results or awards. Tandems bikes are allowed but will not be eligible for an individual award category.
11:00 am – Half Fat Overall Awards
11:30 am – Big Fat Overall Awards
12:00-12:30 pm – Age Group Awards
*Awards will be given on a rolling schedule – must be present to receive your award!
Overall Trophies will be presented to the first three male & female finishers of the Big Fat and Half Fat races.
Age Class Awards will be given to the 1st, 2nd and 3rd place riders, male and female, in each age class for the Fat Bike Races.
Event photos provided by Once In A Blue Moon Studio – Kelly Randolph Photography. View Fat Bike Birkie photos here. >>
