Track guide · Preview · 3 of 16 corners open

Thunderhill East

Willows, California · 4.60 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 85 km/h (53 mph), and the fastest point of the lap arrives at Turn 9, where the model holds 118 km/h (73 mph) mid-corner after a 174 km/h (108 mph) entry. The slow work is concentrated at the Turn 6-7 complex — an 82 km/h (51 mph) simulated minimum — and again in the closing sequence, where Turns 12-13 and 15-16 drop to 72 km/h (45 mph) and, at the lap's tightest corner, 53 km/h (33 mph). Simulated lap times range from 126.3 s on a liter bike to 130 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, 118 km/h (73 mph) minimum
  • Slowest corner (simulated): Turn 15, 53 km/h (33 mph) minimum
  • Simulated lap time, Supersport 600: 127.0 s at 129 km/h (80 mph) average
  • Simulated lap time, liter bike: 126.3 s; middleweight twin: 130 s
  • Longest simulated braking zone: ~87 m into Turn 7 (liter bike)

Turn 1

Left150 m arc
EntryMinExitBrake startEff. radiusElev Δ
126 km/h78 mph110 km/h69 mph129 km/h80 mph42 m138 ft80 m264 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

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

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Turn 2

Left255 m arc
EntryMinExitBrake startEff. radiusElev Δ
117 km/h73 mph86 km/h53 mph139 km/h86 mph6 m20 ft49 m159 ft+1.7 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 3

Right231 m arc
EntryMinExitBrake startEff. radiusElev Δ
122 km/h76 mph93 km/h58 mph120 km/h75 mph33 m108 ft57 m188 ft-4.0 m-13 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

Left66 m arc
EntryMinExitBrake startEff. radiusElev Δ
109 km/h67 mph102 km/h63 mph106 km/h66 mph18 m59 ft68 m223 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

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

Left42 m arc
EntryMinExitBrake startEff. radiusElev Δ
108 km/h67 mph104 km/h65 mph116 km/h72 mph45 m148 ft71 m234 ft+1.7 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 6

Left90 m arc
EntryMinExitBrake startEff. radiusElev Δ
146 km/h91 mph83 km/h52 mph97 km/h60 mph0 m0 ft46 m151 ft+6.8 m+22 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

Right186 m arc
EntryMinExitBrake startEff. radiusElev Δ
93 km/h58 mph82 km/h51 mph129 km/h80 mph87 m285 ft44 m146 ft-12.1 m-40 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 right-hand half of the 6-7 switchback runs tighter than its partner — 44 m effective radius within the shared 276 m, net 5.3 m-descending section — and carries its own simulation estimates: 87 m of braking, an 82 km/h (51 mph) minimum, and a climb back to 129 km/h (80 mph) at the exit for the faster classes. Engine output separates the bike classes only modestly here in the model. The middleweight twin arrives at the same 82 km/h (51 mph) and gives up a couple of km/h at the exit, yet every class shares the identical apex speed because the corner radius, not power, sets the floor.

Turn 8

Left171 m arc
EntryMinExitBrake startEff. radiusElev Δ
140 km/h87 mph92 km/h57 mph128 km/h79 mph15 m49 ft56 m185 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

Left99 m arc
EntryMinExitBrake startEff. radiusElev Δ
174 km/h108 mph118 km/h73 mph129 km/h80 mph12 m39 ft92 m300 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 10

Left111 m arc
EntryMinExitBrake startEff. radiusElev Δ
134 km/h83 mph105 km/h65 mph120 km/h75 mph51 m167 ft74 m241 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

Left129 m arc
EntryMinExitBrake startEff. radiusElev Δ
146 km/h91 mph102 km/h64 mph132 km/h82 mph60 m197 ft69 m226 ft+4.1 m+13 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

Still climbing — 4.1 m of gain over 129 m — Turn 11 tightens to a 69 m effective radius left. The simulated braking zone is disproportionately long for the speed involved: 60 m on the 600 and a full 75 m on the liter bike, from an entry of 146 km/h (91 mph) down to a 102 km/h (63 mph) minimum. The twin manages with 33 m. Exit builds back to 132 km/h (82 mph), or 131 km/h (81 mph) on the twin. Together with Turn 10 this corner caps the sustained uphill stretch on the back half of the lap; from here the elevation trace begins working its way back down toward the finish.

Turn 12

Left84 m arc
EntryMinExitBrake startEff. radiusElev Δ
93 km/h58 mph72 km/h45 mph107 km/h67 mph42 m138 ft34 m112 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 13

Right81 m arc
EntryMinExitBrake startEff. radiusElev Δ
104 km/h65 mph86 km/h54 mph105 km/h65 mph54 m177 ft49 m161 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

The right-hand counterpart to Turn 12 completes the direction change, and in the physics model it carries its own set of estimates: a 49 m effective radius inside the 165 m, gently descending complex, a 104 km/h (65 mph) entry, 54 m of braking, and an 86 km/h (53 mph) floor. Every class posts the same minimum here — radius-limited corners equalize the field in the simulation — and the differences only reappear on the drive out, where the 600 and liter bike edge the twin's 105 km/h (65 mph) by under a km/h. The left-right flip means the modeled line treats 12 and 13 as a linked S-shaped event rather than fully independent corners.

Turn 14

Left66 m arc
EntryMinExitBrake startEff. radiusElev Δ
117 km/h73 mph115 km/h71 mph138 km/h86 mph45 m148 ft87 m285 ft-0.7 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

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

Right156 m arc
EntryMinExitBrake startEff. radiusElev Δ
118 km/h73 mph53 km/h33 mph122 km/h76 mph51 m167 ft19 m61 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 16

Right150 m arc
EntryMinExitBrake startEff. radiusElev Δ
122 km/h76 mph104 km/h65 mph118 km/h74 mph15 m49 ft71 m233 ft-1.2 m-4 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 →