Buttonwillow Raceway Park
Buttonwillow, California · 4.95 km · 3.08 mi · clockwise
Buttonwillow Raceway Park in Buttonwillow, California is a 4,950 m (3.08 mi) clockwise circuit with 13 numbered corners and almost no vertical relief: the simulated elevation band spans just 77 m to 78.1 m, a total gain of 1.6 m. The speed profile splits the lap into two distinct halves. The fast side runs through Turn 2 and Turn 13 (Riverside), where the model carries minimums of 144 km/h (89 mph) and 137 km/h (85 mph) respectively, with Riverside entered at a lap-high 176 km/h (109 mph) on the supersport-600 estimate. The slow side is the Turn 4 through Turn 7 complex — Pacific, Bus Stop, Atlantic — where simulated minimums collapse to roughly 30-31 km/h (18-19 mph), the tightest points on the lap. Simulated lap times run 123.0 s (liter bike) to 130.4 s (middleweight twin); all figures are physics-simulation estimates.
All figures: physics-simulation estimates · generated 2026-07-08 · methodology & assumptions
Track outline © OpenStreetMap contributors (ODbL)
Buttonwillow Raceway Park — quick facts
Motorcycle track guide · simulation estimates · 2026-07-08
- Length: 4,950 m (3.08 mi), run clockwise in this configuration
- 13 numbered corners; elevation range 77-78.1 m (only 1.6 m of total gain)
- Simulated lap times: 123.04 s (liter bike), 125.51 s (supersport 600), 130.35 s (middleweight twin) — physics-simulation estimates
- Simulated average speeds: 137-145 km/h (85-90 mph) depending on bike class
- Fastest simulated corner entry: Turn 13 (Riverside) at ~176 km/h (109 mph)
- Slowest simulated points: Turns 4-7 complex, minimums near 30 km/h (19 mph)
- Track outline (c) OpenStreetMap contributors (ODbL)
Turn 1 — Star Mazda Turn
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 120 km/h75 mph | 74 km/h46 mph | 124 km/h77 mph | 162 m531 ft | 36 m119 ft | +0.0 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
The lap opens with a 144 m right-hander built around a 36.3 m effective radius. In the supersport-600 simulation the model begins braking 162 m before the corner, arriving at 120 km/h (75 mph) and bottoming out at a 74 km/h (46 mph) minimum before climbing back to 124 km/h (77 mph) on exit. The braking distance is the clearest class differentiator here: the liter-bike estimate starts slowing 222 m out because it arrives with more speed to shed potential, while the middleweight twin needs only 111 m. Minimum speed is identical across all three classes — the corner radius, not power, sets the floor. All figures are simulation estimates.
Turn 2
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 162 km/h101 mph | 144 km/h89 mph | 159 km/h99 mph | 0 m0 ft | 136 m447 ft | +0.0 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
Turn 3 — Sunset
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 133 km/h83 mph | 90 km/h56 mph | 133 km/h83 mph | 102 m335 ft | 53 m175 ft | +0.0 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
Sunset is a 135 m left-hander on a 53.4 m effective radius, and the model treats it as a classic medium-speed corner: brake, rotate, drive. The supersport-600 estimate starts braking 102 m out, enters at 133 km/h (83 mph), holds a 90 km/h (56 mph) minimum, and exits at essentially the same 133 km/h it arrived with — a near-symmetric speed trace. Class differences again show up only in brake-application distance: 126 m for the liter bike against 78 m for the twin, with all three bikes sharing the identical 90 km/h grip-limited floor. These are physics-simulation estimates, not measured data.
Turn 4 — Pacific
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 132 km/h82 mph | 31 km/h19 mph | 62 km/h38 mph | 42 m138 ft | 6 m21 ft | +0.0 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
Turn 5 — Bus Stop
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 132 km/h82 mph | 31 km/h19 mph | 62 km/h38 mph | 42 m138 ft | 6 m21 ft | +0.0 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
Turn 6 — Atlantic
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 146 km/h90 mph | 30 km/h18 mph | 136 km/h85 mph | 0 m0 ft | 6 m19 ft | +0.3 m+1 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 |
|---|---|---|---|---|---|
| 146 km/h90 mph | 30 km/h18 mph | 136 km/h85 mph | 0 m0 ft | 6 m19 ft | +0.3 m+1 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 — Sunrise
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 140 km/h87 mph | 100 km/h62 mph | 145 km/h90 mph | 39 m128 ft | 66 m218 ft | +0.3 m+1 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 |
|---|---|---|---|---|---|
| 94 km/h59 mph | 49 km/h30 mph | 92 km/h57 mph | 108 m354 ft | 16 m52 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
Turn 9 is the shortest corner in the dataset — just 60 m of right-hand arc — but its 15.9 m effective radius makes it a genuine interruption. The simulation begins braking 108 m out in the supersport-600 estimate, well over a hundred meters of deceleration for sixty meters of corner, dropping from 94 km/h (59 mph) at entry to a 49 km/h (30 mph) minimum before recovering to 92 km/h (57 mph). Entry speeds are nearly identical across classes because the preceding section is grip-limited rather than power-limited; only the brake point moves, from 90 m (twin) to 114 m (liter bike). Estimates from the physics simulation.
Turn 10 — Cotton Corners
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 137 km/h85 mph | 94 km/h59 mph | 123 km/h76 mph | 72 m236 ft | 58 m192 ft | -0.3 m-1 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 11
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 137 km/h85 mph | 94 km/h59 mph | 128 km/h80 mph | 72 m236 ft | 58 m192 ft | -0.4 m-1 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 12 — Grapevine
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 137 km/h85 mph | 94 km/h59 mph | 147 km/h91 mph | 72 m236 ft | 58 m192 ft | -0.5 m-2 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 13 — Riverside
| Entry | Min | Exit | Brake start | Eff. radius | Elev Δ |
|---|---|---|---|---|---|
| 176 km/h109 mph | 137 km/h85 mph | 164 km/h102 mph | 99 m325 ft | 124 m407 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