Thompson Speedway road course · 11 corners · 29 clean-pace laps on the ZX-4RR, 31 Aug 2026 · the Tiger day of 8 Sep 2025 as the reference

Thompson on the ZX-4RR: what the day said, corner by corner.

Eric Wood's framework sorts every corner into a roll-speed, drive or entrance line from two things: the corner's minimum speed against the bike's threshold-of-traction speed, and how much straight the exit feeds. This page runs that on Thompson's measured geometry for the ZX-4RR and puts the lines you actually rode on it — seven sessions, 29 clean-pace laps, best 1:49.36 — beside the prescription. The plan you rode in with was built from the 2025 Tiger day (best 1:44.40); where this page quotes a Tiger number it is that page's.

The circuit, sorted

roll speeddriveentrance

How the sorting works

V_min vs V_TOT. If the corner's minimum speed is above the speed at which the bike can spin the rear at full lean, horsepower can't hurt you there: take the roll-speed line — maximum radius, apex at the arc's centre, slowest point at the apex, light trail brake to it. Below V_TOT, the throttle becomes the limiting input and the corner is about the exit.

What follows the exit. A long straight rewards exit speed for many seconds: drive line — enter wide, apex late, gas-on-bike-up to the outside edge. Another turn right after gives the exit nothing to cash in: entrance line — brake deep, apex early, slowest point after the apex, set up the next turn.

The advantage runs to the next corner you brake for — read off the speed profile, not off V_TOT. Extra exit speed is banked up to the next braking point and no further, so what matters is where the median profile next dips. At Thompson three pairs never dip between their numbered halves: T1→T2 (0 km/h), T5→T6 (0.5) and T8→T9→T10 (9–11, a roll-off). Those are one corner each, judged at the last exit on the pair's lowest minimum — T2's 64 km/h "minimum" is you still accelerating out of T1. The plan page's first version took V_min below V_TOT to mean "brakes here", split every pair, and called nine corners "entrance"; it also let a roll-speed corner extend the chain (T10 paying "through T11" for 29 s at 70 km/h), which the profile contradicts — you shed 15 km/h for T11 whatever the bike.

A short run is not automatically an entrance corner. With under 5 s to the next braking point the book asks whether the next corner is worth more than this exit: clearly slower (T3 → T4, 61 vs 40 km/h), or feeding a much longer run (T8/T9/T10 → T11 → the main straight). If neither — T4 → T5/T6, T7 → T8 — the exit still pays, just less, and it stays a drive corner. Only when braking starts as the corner ends (under 1.5 s) is the exit worth nothing.

The thresholds are ours, not the framework's: "long straight" = at least 5 s to the next braking corner on the median speed profile, "brakes" = the profile dips at least 12 km/h before the next slowest point, "linked" = the next turn-in within 80 m, "slower" = 10 km/h, "much longer" = 2×. V_TOT for the ZX-4RR is 80 km/h as set in the app (the framework's 400-class figure); the app's modelled value from the ZX's Palmer WOT curves is 66–73 km/h, and the second map shows what 70 does here. The Thompson sessions themselves bound V_TOT at ≤ 85–111 km/h (you never spun the rear, so every grip number is a floor) and model it at 40–49 km/h — but that model reads the WOT fit far below the speeds the ZX was actually at full throttle upright here (75 km/h and up), is flagged as an extrapolation, and is not used. Minimum speeds on this page are the ZX day's own: the median of all 40 counted laps per corner.

Corner by corner: the book vs your ZX lines

"Your line" is the median of the day's 29 clean-pace laps, read in the road frame: where your apex sits against the arc's centre, and where your slowest point sits against your apex. A drive-shaped line apexes past the centre with the slowest point before it; roll-shaped apexes at the centre with the slowest point there; entrance-shaped apexes early with the slowest point after. Lean-corrected to the contact patch and aligned for each day's GPS bias.

Each corner

Strip: your median line through the corner per session, inside limit at the bottom, outside at the top; the tinted band is the tarmac, warm ticks are kerbs, the dashed vertical is the arc's centre. 10:25 (first session) dashed, 17:27 (last) bold, the others grey. Targets: the bar is the share of laps meeting the framework's target for the corner's strategy; the number is how much faster (or slower) those laps exited than the laps that didn't, relative to the day's median — the framework's prescription checked against your own data. "—" = fewer than 3 laps on one side.

Does the book pay? All corners pooled (ZX day, 29 laps)

Per target: the median across corners of "exit speed of laps meeting it minus laps not meeting it" (each relative to its day), and how many corners it helps or hurts by at least 1 km/h. Read this before taking any single corner's number seriously.

What this says

Grain of salt

V_TOT is the softest number on the page, but at Thompson it now moves little. No corner's ZX minimum is above 80 km/h, so the set map has no roll-speed corner; at 70 only T8 (73) and T11 (71) cross. The ZX sessions bound V_TOT at ≤ 85–111 km/h and the Thompson-fitted model (40–49) is an extrapolation we don't use; 70 is the Palmer-modelled figure standing in.
29 laps in seven sessions on a bike you had ridden for one day. The first session is 14 % off the day's best and the last two faded; the medians are of the whole day, not of the good hour. Read shapes, not decimals.
The arc centre is not a recommendation. It is the framework's reference point ("apex 5–20 ft later than the centre" for a drive line). On a 150° hairpin the centre is mid-arc by construction; what a coach would call the apex may legitimately sit elsewhere.
Exit speed relative to the day's median is a blunt response. GPS is good to ~1 km/h; most per-target deltas are 1–3 km/h on 10–40 laps. The pooled table is the honest read; single-corner numbers under ±1 km/h are noise.
Body position, bar pressure, vision — the framework's other half — are invisible to a GPS/IMU/OBD logger. What is measured here is the consequence: lean re-added after the crack, throttle closures, roll-off shape.