Willow Springs (Big Willow)
Rosamond, California · 3.94 km · 2.45 mi · clockwise
Willow Springs (Big Willow) in Rosamond, California is a 3,945 m (2.45 mi) clockwise circuit with ten numbered corners and roughly 59 m (194 ft) of climbing per lap between 736.3 m and 784.4 m (2,416–2,573 ft) elevation. The simulated speed profile splits the lap into two characters. The first half is a sustained high-speed climb: Turns 2 through 4 form a long right-hand arc where the model never drops below 99 km/h (62 mph), gaining about 3 m of elevation across three linked sections. The slow work is concentrated at the top of the hill — Turn 5 and Turn 6 are the only corners with simulated minimums under 95 km/h (59 mph), bottoming at 91 and 75 km/h (56 and 47 mph). From there the lap runs downhill and fast through Turns 7–10, peaking at a 160 km/h (100 mph) simulated entry to Turn 10. Estimated lap times range from 88.0 s (liter bike) to 92.6 s (middleweight twin) — all figures are physics-simulation estimates, not measured data.
All figures: physics-simulation estimates · generated 2026-07-08 · methodology & assumptions
Track outline © OpenStreetMap contributors (ODbL)
Willow Springs (Big Willow) — quick facts
Motorcycle track guide · simulation estimates · 2026-07-08
- Length: 3,945 m (2.45 mi), 10 corners, run clockwise
- Elevation: 736.3–784.4 m (2,416–2,573 ft), about 59 m (194 ft) of gain per lap
- Simulated lap times: 88.0 s (liter bike), 89.6 s (supersport 600), 92.6 s (middleweight twin) — physics-simulation estimates
- Simulated average speeds: 153.3–161.3 km/h (95–100 mph) depending on bike class
- Slowest simulated point: Turn 6 at 75 km/h (47 mph) minimum
- Fastest simulated corner entry: Turn 2 at 168 km/h (104 mph)
- Turns 2–4 form a linked right-hand climb where simulated speed never falls below 99 km/h (62 mph)
Turn 1
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 141 km/h87 mph | 115 km/h72 mph | 149 km/h93 mph | 129 m423 ft | 88 m290 ft | +1.4 m+5 ft |
Supersport 600 preset · simulation estimates · liter-bike and 650-twin figures for every corner ship in the all-access pack · how these are computed
The lap opens with a 192 m left-hander of roughly 88.3 m effective radius, nearly flat at +1.4 m of elevation change. In the simulation the corner is a genuine braking event: the supersport 600 arrives at 141 km/h (87 mph), begins slowing about 129 m before the corner, and touches a 115 km/h (72 mph) minimum before building back to 149 km/h (93 mph) at the exit. The liter bike carries the same entry and minimum speeds but the model starts its braking earlier, at roughly 183 m out, reflecting the higher straightline speed it must shed on approach. The middleweight twin needs only about 84 m of braking and exits slightly slower at 145 km/h (90 mph). All figures are physics-simulation estimates.
Turn 2
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 168 km/h104 mph | 105 km/h65 mph | 104 km/h65 mph | 54 m177 ft | 81 m266 ft | -1.4 m-5 ft |
Supersport 600 preset · simulation estimates · liter-bike and 650-twin figures for every corner ship in the all-access pack · how these are computed
Turn 3
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 104 km/h65 mph | 100 km/h62 mph | 145 km/h90 mph | 150 m492 ft | 65 m214 ft | +1.4 m+5 ft |
Supersport 600 preset · simulation estimates · liter-bike and 650-twin figures for every corner ship in the all-access pack · how these are computed
The shortest measured corner section on the lap, Turn 3 runs 81 m at a tighter 65.3 m effective radius than Turn 2 while gaining 1.4 m of elevation. In the simulation the two corners blend into one continuous state: entry at roughly 104 km/h (65 mph), matching Turn 2's exit, then a 100 km/h (62 mph) minimum, and braking zones of 123–165 m across the classes. The estimated exit speed of 145 km/h (90 mph) is markedly higher than Turn 2's, with only a gentle 1.4 m rise to sap drive through the short arc. Grade affects normal load and available drive in the simulation, but the near-flat profile here barely moves the numbers. Physics-simulation estimates throughout.
Turn 4
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 158 km/h98 mph | 138 km/h86 mph | 153 km/h95 mph | 0 m0 ft | 125 m411 ft | +2.8 m+9 ft |
Supersport 600 preset · simulation estimates · liter-bike and 650-twin figures for every corner ship in the all-access pack · how these are computed
Turn 5
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 124 km/h77 mph | 91 km/h56 mph | 107 km/h66 mph | 84 m276 ft | 55 m180 ft | +18.2 m+60 ft |
Supersport 600 preset · simulation estimates · liter-bike and 650-twin figures for every corner ship in the all-access pack · how these are computed
The character of the lap changes abruptly here. Turn 5 is a 201 m left at a tight 54.9 m effective radius that still climbs 18.2 m — the steepest slow corner on the track. The simulation brakes hard: from a 124 km/h (77 mph) entry, the supersport sheds speed over about 84 m (99 m for the liter bike, 63 m for the twin) down to a 91 km/h (56 mph) minimum, the second-slowest point of the lap. The uphill grade helps the model's braking but limits the estimated exit, which reaches only 107 km/h (66 mph) in every class, since the drive out is still fighting the last of the hill. Simulation estimates only.
Turn 6
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 98 km/h61 mph | 75 km/h47 mph | 136 km/h85 mph | 15 m49 ft | 38 m125 ft | -2.4 m-8 ft |
Supersport 600 preset · simulation estimates · liter-bike and 650-twin figures for every corner ship in the all-access pack · how these are computed
Turn 7
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 136 km/h85 mph | 135 km/h84 mph | 138 km/h86 mph | 51 m167 ft | 120 m395 ft | -11.6 m-38 ft |
Supersport 600 preset · simulation estimates · liter-bike and 650-twin figures for every corner ship in the all-access pack · how these are computed
Turn 8
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 125 km/h78 mph | 105 km/h65 mph | 135 km/h84 mph | 21 m69 ft | 73 m239 ft | -4.8 m-16 ft |
Supersport 600 preset · simulation estimates · liter-bike and 650-twin figures for every corner ship in the all-access pack · how these are computed
Turn 9
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 150 km/h93 mph | 144 km/h89 mph | 168 km/h104 mph | 12 m39 ft | 136 m448 ft | -2.1 m-7 ft |
Supersport 600 preset · simulation estimates · liter-bike and 650-twin figures for every corner ship in the all-access pack · how these are computed
Turn 10
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 160 km/h100 mph | 130 km/h81 mph | 150 km/h93 mph | 3 m10 ft | 111 m365 ft | -0.1 m-0 ft |
Supersport 600 preset · simulation estimates · liter-bike and 650-twin figures for every corner ship in the all-access pack · how these are computed