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 modeled here as the 3-mile Cyclone layout, the motorcycle configuration that keeps Turn 5 rather than the bypass: a 4,604 m (2.86 mi) counterclockwise lap over the official 15-turn card, with Turn 5A splitting the Cyclone's descent from the corner itself. The physics simulation puts the fastest point at Turn 7, a 214.3 m radius left held at 180.3 km/h (112 mph), and the slowest at The Cyclone, where the model drops to 56.3 km/h (35 mph) before falling 9.2 m through 5A. Simulated lap times range from 112.3 s on a liter bike to 117.7 s on a middleweight twin. All figures on this page are physics-simulation estimates.

All figures: physics-simulation estimates · generated 2026-10-02 · methodology & assumptions

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

Track outline © OpenStreetMap contributors (ODbL)

Thunderhill East — quick facts

Motorcycle track guide · simulation estimates · 2026-10-02

  • Layout: East Course (3-mile Cyclone configuration), 4,604 m (2.86 mi), run counterclockwise
  • Turn card: 15 numbered turns plus 5A; Turn 5 is named The Cyclone
  • Fastest corner (simulated): Turn 7, 180.3 km/h (112 mph) minimum
  • Slowest corner (simulated): Turn 5 — The Cyclone, 56.3 km/h (35 mph) minimum on a 21 m effective radius
  • Simulated lap time, Supersport 600: 113.9 s at 143.9 km/h (89 mph) average
  • Simulated lap time, liter bike: 112.3 s; middleweight twin: 117.7 s
  • Longest simulated braking zone: 168 m into Turn 14 (liter bike)
  • Biggest descent: Turn 5A drops 9.2 m; biggest climb: Turn 8 gains 5.3 m

Turn 1

Left165 m arc
EntryMinExitBrake startEff. radiusElev Δ
161 km/h100 mph131 km/h81 mph157 km/h98 mph108 m354 ft113 m370 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 112.8 m effective radius that climbs 2.7 m over its 165 m length. In the simulation a Supersport 600 arrives at 161.1 km/h (100 mph), begins braking 108 m before the corner, and carries a 130.7 km/h (81 mph) minimum before running out at 157.2 km/h (98 mph). Bike class changes the brake point far more than the corner speed: the liter bike's straight-line speed pushes its simulated brake marker out to 159 m, while the middleweight twin needs only 66 m and exits at 154.1 km/h (96 mph). All three classes share the same 130.7 km/h apex figure.

Turn 2

Left294 m arc
EntryMinExitBrake startEff. radiusElev Δ
142 km/h88 mph113 km/h70 mph143 km/h89 mph69 m226 ft84 m276 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

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

Right186 m arc
EntryMinExitBrake startEff. radiusElev Δ
140 km/h87 mph108 km/h67 mph126 km/h78 mph39 m128 ft76 m250 ft-4.7 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

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

Left102 m arc
EntryMinExitBrake startEff. radiusElev Δ
118 km/h73 mph90 km/h56 mph121 km/h75 mph15 m49 ft53 m175 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 →

Turn 5 — The Cyclone

Left36 m arc
EntryMinExitBrake startEff. radiusElev Δ
78 km/h48 mph56 km/h35 mph84 km/h52 mph51 m167 ft21 m69 ft-0.2 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

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 5A

Right165 m arc
EntryMinExitBrake startEff. radiusElev Δ
97 km/h60 mph89 km/h55 mph142 km/h88 mph96 m315 ft52 m170 ft-9.2 m-30 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

Left156 m arc
EntryMinExitBrake startEff. radiusElev Δ
133 km/h83 mph99 km/h62 mph143 km/h89 mph30 m98 ft65 m213 ft+1.1 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 →

Turn 7

Left123 m arc
EntryMinExitBrake startEff. radiusElev Δ
182 km/h113 mph180 km/h112 mph187 km/h116 mph12 m39 ft214 m703 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 8

Left114 m arc
EntryMinExitBrake startEff. radiusElev Δ
168 km/h104 mph140 km/h87 mph160 km/h99 mph51 m167 ft129 m422 ft+5.3 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 9

Left102 m arc
EntryMinExitBrake startEff. radiusElev Δ
124 km/h77 mph97 km/h60 mph133 km/h83 mph84 m276 ft62 m205 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

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

Left117 m arc
EntryMinExitBrake startEff. radiusElev Δ
124 km/h77 mph90 km/h56 mph129 km/h80 mph114 m374 ft54 m177 ft-5.4 m-18 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 is a 117 m left at a 53.8 m effective radius that falls 5.4 m — giving back everything Turn 8 gained. The simulation's brake zone is one of the longest on the track: 114 m on the 600, 141 m on the liter bike and 81 m on the twin, from a 124.3 km/h (77 mph) entry to a 90.5 km/h (56 mph) minimum. The downhill grade reduces available braking load in the model's assumptions, which stretches the zone well beyond what the 34 km/h speed drop alone would need. Exit is estimated at 128.7 km/h (80 mph) on the faster classes and 126.4 km/h (79 mph) on the twin.

Turn 11

Left60 m arc
EntryMinExitBrake startEff. radiusElev Δ
77 km/h48 mph65 km/h40 mph94 km/h58 mph48 m157 ft28 m91 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 12

Right48 m arc
EntryMinExitBrake startEff. radiusElev Δ
114 km/h71 mph114 km/h71 mph125 km/h78 mph54 m177 ft86 m282 ft-0.6 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 13

Left75 m arc
EntryMinExitBrake startEff. radiusElev Δ
139 km/h86 mph131 km/h82 mph165 km/h102 mph12 m39 ft114 m373 ft-1.1 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 →

Turn 14

Right105 m arc
EntryMinExitBrake startEff. radiusElev Δ
104 km/h65 mph70 km/h44 mph102 km/h64 mph135 m443 ft32 m106 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 14 carries the longest braking zone on the circuit: 135 m on the 600, 168 m on the liter bike and 99 m on the twin, from a 104.5 km/h (65 mph) entry to a 70.2 km/h (44 mph) minimum. The corner itself is a 105 m right at a 32.4 m effective radius, descending 2.4 m. The brake figures reflect the speed built out of Turn 13 rather than the modest entry number, since the model is still slowing as it arrives. Exit is estimated at 102.4 km/h (64 mph) on the faster classes and 101.6 km/h (63 mph) on the twin — back to roughly the entry figure, with almost no class spread.

Turn 15

Right108 m arc
EntryMinExitBrake startEff. radiusElev Δ
127 km/h79 mph116 km/h72 mph140 km/h87 mph60 m197 ft89 m292 ft-1.3 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 →