Track guide · Preview · 3 of 16 corners open

Thunderhill East

Willows, California · 4.61 km · 2.86 mi · counterclockwise

Thunderhill Raceway Park's East Course in Willows, California is a 4,605 m (2.86 mi) lap run counterclockwise through 16 numbered corners. Elevation spans 82.9 m to 116 m, and the layout climbs and descends enough to accumulate 60.4 m of gain per lap. The simulated speed profile splits the track into two characters. The opening third is quick: Turns 1 through 3 all carry minimums above 105 km/h (66 mph), and the fastest point of the lap arrives at Turn 9, where the model holds 144 km/h (89 mph) mid-corner after a 167 km/h (104 mph) entry. The slow work is concentrated at the Turn 6-7 complex — the lap's tightest section at a 49 km/h (31 mph) simulated minimum — and again in the closing sequence, where Turns 12-13 and 15-16 drop to 67 km/h (41 mph) and 74 km/h (46 mph). Simulated lap times range from 117.0 s on a liter bike to 122.5 s on a middleweight twin. All figures on this page are physics-simulation estimates.

All figures: physics-simulation estimates · generated 2026-07-08 · methodology & assumptions

COMPUTED LINE · THUNDERHILL EAST SIM
Thunderhill East track map with computed racing line
2.86 MI
Lap
16
Corners
198 FT
Climb

Track outline © OpenStreetMap contributors (ODbL)

Thunderhill East — quick facts

Motorcycle track guide · simulation estimates · 2026-07-08

  • Length: 4,605 m (2.86 mi), run counterclockwise
  • 16 corners; elevation ranges 82.9-116 m with 60.4 m of gain per lap
  • Fastest corner (simulated): Turn 9, 144 km/h (89 mph) minimum
  • Slowest corners (simulated): Turns 6-7, 49 km/h (31 mph) minimum
  • Simulated lap time, Supersport 600: 118.7 s at 139 km/h (87 mph) average
  • Simulated lap time, liter bike: 117.0 s; middleweight twin: 122.5 s
  • Longest simulated braking zone: ~153 m into the Turn 15-16 complex (liter bike)

Turn 1

Left147 m arc
EntryMinExitBrake startEff. radiusElev Δ
151 km/h94 mph118 km/h74 mph147 km/h92 mph117 m384 ft92 m302 ft+2.7 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

The lap opens with a left of roughly 92 m effective radius that climbs 2.7 m over its 147 m length. In the simulation a Supersport 600 arrives at 151 km/h (94 mph), begins braking about 117 m before the corner, and carries a 118 km/h (74 mph) minimum before running back out at 147 km/h (92 mph). Bike class changes the brake point more than the corner speed: the higher straight-line speed of a liter bike pushes the simulated brake marker out to about 168 m, while the middleweight twin needs only around 75 m and exits slightly slower at 143 km/h (89 mph). All three classes share essentially the same 118 km/h apex figure — a simulation estimate, like every number here.

Turn 2

Left321 m arc
EntryMinExitBrake startEff. radiusElev Δ
148 km/h92 mph114 km/h71 mph145 km/h90 mph60 m197 ft85 m279 ft-3.4 m-11 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 3

Right201 m arc
EntryMinExitBrake startEff. radiusElev Δ
153 km/h95 mph106 km/h66 mph131 km/h81 mph30 m98 ft74 m242 ft-4.2 m-14 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 4

Left105 m arc
EntryMinExitBrake startEff. radiusElev Δ
122 km/h76 mph88 km/h55 mph119 km/h74 mph15 m49 ft51 m168 ft+1.0 m+3 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 5

Left105 m arc
EntryMinExitBrake startEff. radiusElev Δ
122 km/h76 mph88 km/h55 mph119 km/h74 mph15 m49 ft51 m168 ft+1.0 m+3 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 6

Left300 m arc
EntryMinExitBrake startEff. radiusElev Δ
141 km/h88 mph49 km/h31 mph154 km/h96 mph63 m207 ft16 m53 ft-4.4 m-14 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 7

Right300 m arc
EntryMinExitBrake startEff. radiusElev Δ
141 km/h88 mph49 km/h31 mph154 km/h96 mph63 m207 ft16 m53 ft-4.4 m-14 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 8

Left153 m arc
EntryMinExitBrake startEff. radiusElev Δ
133 km/h83 mph98 km/h61 mph134 km/h83 mph30 m98 ft63 m208 ft+1.0 m+3 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 9

Left108 m arc
EntryMinExitBrake startEff. radiusElev Δ
167 km/h104 mph144 km/h89 mph160 km/h100 mph27 m89 ft137 m449 ft+2.2 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 10

Left102 m arc
EntryMinExitBrake startEff. radiusElev Δ
147 km/h91 mph117 km/h73 mph140 km/h87 mph54 m177 ft90 m297 ft+5.2 m+17 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 11

Left114 m arc
EntryMinExitBrake startEff. radiusElev Δ
132 km/h82 mph95 km/h59 mph126 km/h78 mph75 m246 ft60 m196 ft+3.8 m+12 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 12

Left162 m arc
EntryMinExitBrake startEff. radiusElev Δ
107 km/h66 mph67 km/h41 mph124 km/h77 mph33 m108 ft29 m96 ft-1.9 m-6 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 13

Right162 m arc
EntryMinExitBrake startEff. radiusElev Δ
107 km/h66 mph67 km/h41 mph124 km/h77 mph33 m108 ft29 m96 ft-1.9 m-6 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 14

Left78 m arc
EntryMinExitBrake startEff. radiusElev Δ
146 km/h91 mph130 km/h81 mph147 km/h91 mph0 m0 ft112 m368 ft-0.8 m-3 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

This corner's walkthrough is in the all-access pack — along with the other 12 locked corners on this track.

Unlock every corner · $59 lifetime →

Turn 15

Right261 m arc
EntryMinExitBrake startEff. radiusElev Δ
120 km/h75 mph74 km/h46 mph137 km/h85 mph120 m394 ft36 m118 ft-4.6 m-15 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 closing complex begins with this right-hander — 36 m effective radius, part of a 261 m double-right section that sheds 4.6 m of elevation on the way to the front straight. The simulation's braking zone here is the longest on the track: about 120 m for the 600 and roughly 153 m on the liter bike, from a 120 km/h (75 mph) entry down to a 74 km/h (46 mph) minimum; the twin needs around 87 m. Exit speed matters more here than anywhere else because the start-finish straight follows, and the model releases the complex at 137 km/h (85 mph) for the faster classes, 133 km/h (83 mph) for the twin — estimates, as throughout.

Turn 16

Right261 m arc
EntryMinExitBrake startEff. radiusElev Δ
120 km/h75 mph74 km/h46 mph137 km/h85 mph120 m394 ft36 m118 ft-4.6 m-15 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 final corner shares its modeled section with Turn 15: two rights totaling 261 m at a 36 m effective radius, descending 4.6 m onto the main straight, with identical per-class estimates — a 74 km/h (46 mph) minimum out of a 120 km/h (75 mph) entry, and an exit of 137 km/h (85 mph) on the 600 and liter bike. Whatever speed the simulation banks here compounds down the full length of the front straight into the ~117-168 m Turn 1 brake zone, which is why the exit figure, not the minimum, is the number that shapes the modeled lap times of 117.0-122.5 s across the three classes.