A hundred miles of southern Arizona gravel, from Patagonia to the Mexican border and back, between four and six thousand feet. Below is the ride the way the model rides it: your finish at three paces, where a fast rider gains on you, the climbs that cost the most, what the altitude takes, and a fuel plan timed to the road.
No card. No account needed to try it.
The organizer's route for the 100 lists 101.8 miles and 6,392 ft in the gravel roads south of Patagonia to the Mexican border. The figures above are the model's own reading of the organizer's 2025 RideWithGPS route for the 100 (the 2026 routes are not posted yet). Time limit 10 hours. The weekend runs an 80, a 58 and a 30.
The rider the app opens with, 185 lb, 280 W FTP, 20 kJ reserve, at the app's three pace settings, beside a fast rider. Your own numbers move all of it.
Riding it steady costs 42 minutes against moderate; riding it aggressive saves 21 minutes and takes your anaerobic reserve down to 71% at its lowest, against 86% at moderate. At 4,073 to 5,819 ft the thinner air takes about 6% off a rider coming from sea level, and that is in these times.
150 lb, 350 W FTP, 28 kJ reserve, aggressive
5:12263 W average, 19.6 mph
185 lb, 280 W FTP, 20 kJ reserve, moderate
6:48178 W average, 15.0 mph
The deficit grows fastest from mile 28 to mile 44, 25 minutes of it in 17 miles. None of the numbered climbs sits in it: it is steady road rather than one big climb, and the fast rider's extra 85 watts turn into speed mile after mile.
| Where | Climb | Grade | Time | Power | |
|---|---|---|---|---|---|
| 1 | 4.4 to 5.7 mi | 162 ft | 2.3% | 6:38 | 204 W |
| 2 | 7.7 to 11.4 mi | 546 ft | 2.8% | 19:59 | 211 W |
| 3 | 19.0 to 19.7 mi | 234 ft | 6.3% | 5:37 | 245 W |
| 4 | 78.1 to 80.1 mi | 233 ft | 2.3% | 9:45 | 205 W |
For the guest rider at moderate pace. Ranked by what each one costs as a share of the ride, not by how tall it looks, then listed in the order you reach them.
About 73 g an hour at moderate pace. Each feed goes in about 20 minutes before the model says you need it, on an easier stretch rather than on a climb, and none in the last 20 minutes, where it could not be absorbed before the line.
| Feed | Mile | Into the ride | Carbohydrate |
|---|---|---|---|
| 1 | 6.1 mi | 0:27 | 15 g |
| 2 | 16.3 mi | 1:18 | 54 g |
| 3 | 26.9 mi | 1:57 | 65 g |
| 4 | 35.4 mi | 2:33 | 60 g |
| 5 | 39.9 mi | 2:55 | 37 g |
| 6 | 50.7 mi | 3:38 | 71 g |
| 7 | 59.7 mi | 4:09 | 52 g |
| 8 | 67.1 mi | 4:37 | 46 g |
| 9 | 74.9 mi | 5:12 | 55 g |
| 10 | 83.7 mi | 5:47 | 45 g |
From the burn the model puts on this course: work along the route, carbohydrate share from the pace, what your glycogen holds for your weight, and 400 kcal an hour through the gut for a glucose and fructose mix. Move the feeds to the aid stations you will actually use; the plan updates.
Set a goal time for the Spirit World 100 and the app reads your recent rides against this course: a likely finish range, its middle, and your goal marked likely, possible, a stretch or unlikely. With a power meter from measured watts; without one, from your speed on your own ground.
What your best riding of each week would finish in on this route, so you can see whether the training is moving the number, not just adding miles.
Each of the climbs above, checked against what you actually ride: covered, mostly covered, thin or not ridden, so the next session goes where the race will hurt.
The route is cut into short segments and each is solved for the speed your power holds against gravity, rolling resistance for the surface, and air, thinner at altitude. On twisting trail your speed is capped by how fast you can corner, and on the far side of a climb you keep the speed you carried in. The time on each segment is added up, the reserve you spend above threshold and win back below it is tracked the whole way, and the carbohydrate is burned where the work is done. It is fitted against recorded races: on a Chequamegon 40 validation ride it predicted 2:24:28 against an actual 2:24:20.
For the guest rider the app opens with (185 lb, 280 W FTP, 20 kJ reserve), the model puts it at 6:48 at moderate pace, 7:30 riding steady and 6:26 riding aggressive. A fast rider at 150 lb, 350 W FTP, 28 kJ reserve is around 5:12. The cutoff is 10 hours. Put your own weight and fitness in and it forecasts yours.
The organizer's route for the 100 lists 6,392 ft for the Spirit World 100. The route file the model rode measures 6,526 ft over 101.7 miles, between 4,073 and 5,819 ft.
Climb 2 on the chart, 7.7 miles in: 546 ft at 2.8%, 19:59 at 211 W for the guest rider at moderate pace.
At moderate pace the plan is 500 g of carbohydrate over the ride, about 73 g an hour, in 10 feeds. Each goes in about 20 minutes before the model says you need it, on an easier stretch, and the last is at mile 84 so it is absorbed before the line.
The model rode it as dirt road throughout, on a gravel bike. The organizer describes a gravel road network through three distinct ecological zones between Patagonia and the Mexican border. Surface is worth 13 to 17% of a finish time, so tag the sections in the app and the forecast follows.
Yes. Load the route and run the whole plan as a guest, no account. Pro ($9 a month, or $59 a year) adds saved routes and plans, a saved athlete profile and the head unit export.
Same model, one page per course.
Same course, your weight, your fitness, your pace. Two minutes of setup now.