[{"data":1,"prerenderedAt":1578},["ShallowReactive",2],{"crumb-\u002Fstories\u002Fright-turns-lean-further":3,"stories-\u002Fstories\u002Fright-turns-lean-further":4,"more-to-read":59},"Right turns lean further",{"id":5,"title":3,"body":6,"date":47,"description":48,"draft":49,"extension":50,"image":18,"imageAlt":51,"kicker":52,"meta":53,"navigation":54,"path":55,"pinned":49,"seo":56,"stem":57,"__hash__":58},"stories\u002Fstories\u002Fright-turns-lean-further.md",{"type":7,"value":8,"toc":43},"minimark",[9,13,22,25,28,31,34],[10,11,12],"p",{},"On September 29, a camera fixed to the frame recorded the bike's lean through every drill. In every drill that turned both ways, Rich leaned further going right than going left, by 2 to 6 degrees in most of them.",[14,15,19],"fn-plate",{":chart":16,"alt":17,"src":18},"true","Median peak lean in left and right turns for each drill, right leaning further","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fleft-right.svg",[10,20,21],{},"Median peak lean per turn, left in blue and right in orange. The labels give each side's median turn radius in meters and the number of turns.",[10,23,24],{},"A motorcycle in a steady turn needs a certain amount of lean. It depends on how fast the bike is going and how tight the turn is. It doesn't depend on which way the bike is turning. A right turn and a left turn at the same speed and size need the same lean.",[10,26,27],{},"The turns were about the same size both ways, 6 to 7 meters (20 to 23 feet) in radius. In the figure eight and the dual U-turn, the right turns were slightly wider, which should have needed less lean, not more.",[10,29,30],{},"So the difference isn't the physics. It's the rider. Plenty of riders have a side they favor, and the fix is simple: ride more of the harder side. The hard part is knowing which side that is. That's the kind of thing MotoDrill should be able to point out.",[10,32,33],{},"This is one session, one rider and a handful of turns each way. It's a first look, not a verdict.",[10,35,36,37,42],{},"The full write-up, with every chart: ",[38,39,41],"a",{"href":40},"\u002Ffield-notes\u002F2026-09-29-countersteer\u002F","Countersteer, caught on two cameras",".",{"title":44,"searchDepth":45,"depth":45,"links":46},"",2,[],"2026-10-02","In every turning drill, Rich leaned a few degrees more going right than going left. The physics says he shouldn't, which makes it something to practice.",false,"md","Peak lean in left and right turns for each drill, right leaning further",null,{},true,"\u002Fstories\u002Fright-turns-lean-further",{"title":3,"description":48},"stories\u002Fright-turns-lean-further","7L6RbVFZZ3FYGZYYG9CAZInz4cvG_mEV4VdJXMPI7L4",[60,115,140,180,1179],{"id":61,"title":62,"body":63,"date":47,"description":107,"draft":49,"extension":50,"image":71,"imageAlt":108,"kicker":52,"meta":109,"navigation":54,"path":110,"pinned":49,"seo":111,"stem":112,"__hash__":113,"kind":114},"stories\u002Fstories\u002Ffive-hard-stops.md","Five hard stops",{"type":7,"value":64,"toc":105},[65,68,75,82,88,91,94,100],[10,66,67],{},"Emergency braking is a drill with a number at the end of it: how quickly the bike stops. On September 29, Rich rode five hard stops from 21 to 27 mph, and two sensors measured them.",[14,69,72],{":chart":16,"alt":70,"src":71},"Stopping distance, entry speed and peak deceleration for five emergency stops","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fbraking.svg",[10,73,74],{},"Stopping distance from the moment the brakes came on, with entry speed and peak deceleration for each stop.",[10,76,77,81],{},[78,79,80],"strong",{},"GPS gave the speed."," A phone's GPS position wanders too much to measure a parking-lot drill, but its speed is good to a fraction of a mile per hour. That gave the entry speed for every stop.",[10,83,84,87],{},[78,85,86],{},"A camera fixed to the frame gave the deceleration."," Its own motion sensor recorded how hard the bike slowed, a thousand times a second.",[10,89,90],{},"The brakes came on hard and fast: 80% of peak deceleration within 0.2 to 0.3 seconds, every time. Peaks reached 0.73 to 0.82 g. The last few miles per hour came off gently, so the average over a whole stop was only about half the peak.",[10,92,93],{},"For comparison, eleven ordinary traffic stops on the road that day peaked at 0.14 to 0.34 g. The gap between an everyday stop and an emergency stop is exactly what the drill trains.",[10,95,96,99],{},[78,97,98],{},"The distances need checking."," The analysis puts the stops at 38 to 55 feet. (Rich still complains that he thinks he stopped quicker than that.) He remembers stopping in under three parking spaces, though maybe not on these runs, so the next step is to measure the lot's stall lines and test again against them.",[10,101,102,103,42],{},"The full write-up: ",[38,104,41],{"href":40},{"title":44,"searchDepth":45,"depth":45,"links":106},[],"Emergency-braking reps, measured with GPS speed and a camera fixed to the frame. The brakes come on fast. How far the bike travels is still an open question.","Stopping distance, entry speed and peak deceleration for five hard stops",{},"\u002Fstories\u002Ffive-hard-stops",{"title":62,"description":107},"stories\u002Ffive-hard-stops","VyMW1IeCRiLP9_-SrCvMMHjjpxEwaegGcNOQoccwh9I","story",{"id":5,"title":3,"body":116,"date":47,"description":48,"draft":49,"extension":50,"image":18,"imageAlt":51,"kicker":52,"meta":138,"navigation":54,"path":55,"pinned":49,"seo":139,"stem":57,"__hash__":58,"kind":114},{"type":7,"value":117,"toc":136},[118,120,124,126,128,130,132],[10,119,12],{},[14,121,122],{":chart":16,"alt":17,"src":18},[10,123,21],{},[10,125,24],{},[10,127,27],{},[10,129,30],{},[10,131,33],{},[10,133,36,134,42],{},[38,135,41],{"href":40},{"title":44,"searchDepth":45,"depth":45,"links":137},[],{},{"title":3,"description":48},{"id":141,"title":142,"body":143,"date":47,"description":173,"draft":49,"extension":50,"image":151,"imageAlt":174,"kicker":52,"meta":175,"navigation":54,"path":176,"pinned":49,"seo":177,"stem":178,"__hash__":179,"kind":114},"stories\u002Fstories\u002Fyour-bars-turn-the-wrong-way-first.md","Your bars turn the wrong way first",{"type":7,"value":144,"toc":171},[145,148,155,158,161,164,167],[10,146,147],{},"To lean a motorcycle into a right turn, the handlebars first turn a little to the left. Then they come back to the right and the bike follows. It's called countersteering. Every rider does it, and most never notice.",[14,149,152],{":chart":16,"alt":150,"src":151},"Average handlebar angle around turn-in at 10 to 20 mph: the bars turn away from the turn first, then into it","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fsteer-hero.svg",[10,153,154],{},"Handlebar angle around turn-in at 10 to 20 mph, averaged over 12 turns. Down is away from the turn. The pink band is the shape countersteering should make; the solid line is what the cameras measured.",[10,156,157],{},"On September 29, Rich rode on the road with two cameras on the bike. One was on the handlebars and turned with them. The other was on a stick fixed to the frame, and didn't. Both cameras record their own motion, so taking one from the other leaves just the steering.",[10,159,160],{},"At 10 to 20 mph, the bars turned away from the turn first in 10 of 12 turn-ins. The average was 0.73 of a degree. That's too small to see and too small to feel, and it was there almost every time.",[10,162,163],{},"These were ordinary road turns, at corners and junctions, not drills. At walking pace the dip looked bigger: about 1.8 degrees, in 9 of 10 turn-ins. That's only ten turns, so it's an early result. If it holds, it fits the physics: a slow bike needs more input to tip it into a lean, and as speed rises the bike steadies itself and needs less. Above 20 mph there were only four turn-ins, not enough to say anything yet.",[10,165,166],{},"One more thing came out of the same session, this time from the drills. At the same speed and the same radius, Rich leans 2 to 6 degrees further in right turns than in left ones. The physics asks for the same lean both ways, so that difference is the rider. It's the kind of thing MotoDrill should be able to point out.",[10,168,36,169,42],{},[38,170,41],{"href":40},{"title":44,"searchDepth":45,"depth":45,"links":172},[],"Two cameras on one ride caught the countersteer every rider does without knowing it. It's less than a degree.","[object Object]",{},"\u002Fstories\u002Fyour-bars-turn-the-wrong-way-first",{"title":142,"description":173},"stories\u002Fyour-bars-turn-the-wrong-way-first","MYBE2FXZ-H9_32QG542tKaUgyVknd_8W_bO7SnOFkvw",{"id":181,"title":41,"body":182,"date":1171,"description":1172,"draft":49,"extension":50,"image":151,"imageAlt":174,"kicker":52,"meta":1173,"navigation":54,"path":1174,"pinned":49,"seo":1175,"stem":1176,"__hash__":1177,"kind":1178},"fieldNotes\u002Ffield-notes\u002F2026-09-29-countersteer.md",{"type":7,"value":183,"toc":1156},[184,187,216,235,320,348,403,956,970,1005,1087,1108],[10,185,186],{},"A handlebar camera and a frame camera recorded together on the road. Subtract one from the other and what remains is the rider's steering. At turn-in the bars go the wrong way first, then into the turn.",[188,189,190,212],"fn-pair",{},[191,192,193,199,209],"fn-col",{},[194,195,196],"fn-big",{},[10,197,198],{},"−0.73°",[200,201,202],"fn-aside",{},[10,203,204,205,208],{},"Mean handlebar angle during roll-in at 10–20 mph, with the bars turned ",[78,206,207],{},"away"," from the turn. 10 of 12 turn-ins, 95% interval −1.1° to −0.4°.",[10,210,211],{},"Also measured this session: the phone's motion sensors failed after 110 seconds, the frame camera stood in for them, and the drills were recognized from their shape alone.",[191,213,214],{":lead":16},[14,215],{"alt":150,"src":151,":chart":16},[217,218,220,225,228],"fn-section",{"eyebrow":219},"What recorded what",[221,222,224],"h2",{"id":223},"the-phone-lost-99-minutes-the-cameras-didnt","The phone lost 99 minutes. The cameras didn't.",[10,226,227],{},"Sensor Logger kept GPS running but stopped every motion sensor two minutes in, and resumed only when the app was reopened to stop it. It is the third time; every failure came in the first two minutes. Two cameras carry their own motion data: the Insta360 X5 on the frame (1,000 samples a second) and the DJI Action 6, on the handlebars for the road legs and on a tripod in the lot.",[14,229,232],{"alt":230,"src":231,":chart":16,":wide":16},"Timeline of what each sensor recorded across the session, with the phone motion data missing for 99 minutes","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fcoverage.svg",[10,233,234],{},"Every drill run (bottom lane, colored by drill) fell inside the phone's gap. Times are Central. The frame camera's clock ran 4.9 s behind the phone (5.7 s after a power cycle); both were aligned from motion, not from file times.",[217,236,238,242,300],{"eyebrow":237},"Cameras as instruments",[221,239,241],{"id":240},"can-a-camera-on-a-selfie-stick-be-a-frame-sensor","Can a camera on a selfie stick be a frame sensor?",[188,243,244,255],{},[191,245,246,249,252],{},[10,247,248],{},"For rotation, yes. A rigid body rotates the same everywhere on it, so the gyro on a stick sees exactly the bike's yaw, roll and pitch. Heading, lean and turn rate all come out clean.",[10,250,251],{},"For acceleration, only partly. The stick puts the camera a meter from the pitch center, so fork dive under hard braking adds about 0.4 g of false spike. The stick also shakes at about 42 Hz, far above anything the rider does, and a filter removes it.",[10,253,254],{},"A better frame sensor for the app would be a phone or small sensor fixed near the tank. The camera proves the idea.",[191,256,257],{},[258,259,260],"fn-stats",{},[261,262,263,270,276,282,288,294],"ul",{},[264,265,266,269],"li",{},[78,267,268],{},"3.4–9.1°"," X5 heading error vs GPS (phone on the bars: 14.8°)",[264,271,272,275],{},[78,273,274],{},"r 0.92"," X5 lean vs lean the physics requires",[264,277,278,281],{},[78,279,280],{},"1.02"," X5 forward-axis gain vs GPS speed change (1.00 is perfect)",[264,283,284,287],{},[78,285,286],{},"r 0.993"," Action 6 vs phone turn rate, same handlebar mount",[264,289,290,293],{},[78,291,292],{},"5.6 s"," to read all five X5 files' motion data over the network, without touching video",[264,295,296,299],{},[78,297,298],{},"13.3°"," bars into a slow 5.9 m U-turn, measured. Geometry predicts ~15°.",[188,301,302,311],{},[191,303,304],{},[14,305,308],{"alt":306,"src":307,":chart":16},"Lean measured by the frame camera against the lean the turn requires, clustered along the diagonal","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Flean-scatter.svg",[10,309,310],{},"Each dot is a moment of riding. Across: the lean a steady turn needs, from speed and turn rate. Up: the lean the frame camera measured. The diagonal is perfect agreement.",[191,312,313],{},[14,314,317],{"alt":315,"src":316,":chart":16},"Turn rate from the Action 6 and the phone over ninety seconds, overlaying almost exactly","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fa6-vs-phone.svg",[10,318,319],{},"Ninety seconds of the ride home. The Action 6 and the phone share the handlebar mount; their turn rates overlay almost exactly. The Action 6 can stand in for the phone.",[217,321,323,327,330,345],{"eyebrow":322},"The headline result, in full",[221,324,326],{"id":325},"steering-by-speed","Steering, by speed",[10,328,329],{},"Each chart lines up every turn-in on the moment the lean passes 3° and flips left turns so that \"toward the turn\" is always up. The pink band is what countersteering should look like: bars away first, then into the turn. The solid line is the measured average with its 95% band; the dashed line is the same average taken at random moments, which should stay flat.",[331,332,333,337,341],"fn-grid",{},[14,334],{"alt":335,"src":336,":chart":16},"Steering around turn-in at walking pace, 4 to 10 mph","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fsteer-band-walking.svg",[14,338],{"alt":339,"src":340,":chart":16},"Steering around turn-in at 10 to 20 mph","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fsteer-band-10-20.svg",[14,342],{"alt":343,"src":344,":chart":16},"Steering around turn-in above 20 mph, only four turn-ins","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fsteer-band-20-plus.svg",[10,346,347],{},"The countersteer gets smaller as speed rises, as physics predicts: a faster bike needs less input to roll. Only 4 turn-ins above 20 mph were recorded, too few to read.",[217,349,351,355,358,365],{"eyebrow":350},"Drills as shapes",[221,352,354],{"id":353},"nine-drills-redrawn-from-motion-alone","Nine drills, redrawn from motion alone",[10,356,357],{},"GPS can't draw a drill: its position error is as big as the drill. The paths below come from the frame camera's heading and the GPS speed, integrated. Color is speed. Under each is the same run written as tokens (L181r6 is a 181° left turn at 6 m radius, S5m a 5 m straight, P2s a 2 s stop). That string doesn't change when the drill moves to another corner of the lot, so it's what the recognizer reads.",[10,359,360],{},[361,362],"img",{"alt":363,"src":364},"Speed colors: blue at walking pace, yellow around 12 mph, orange at 25 mph","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fpaths-legend.svg",[331,366,367,371,375,379,383,387,391,395,399],{},[14,368],{"alt":369,"src":370,":chart":16},"Figure eight 7 path, redrawn from motion, colored by speed","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fpath-01-figure-eight-7.svg",[14,372],{"alt":373,"src":374,":chart":16},"Offset weave 2 path, redrawn from motion, colored by speed","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fpath-02-offset-weave-2.svg",[14,376],{"alt":377,"src":378,":chart":16},"Dual u turn 3 path, redrawn from motion, colored by speed","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fpath-03-dual-u-turn-3.svg",[14,380],{"alt":381,"src":382,":chart":16},"Fixed circle 3 path, redrawn from motion, colored by speed","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fpath-04-fixed-circle-3.svg",[14,384],{"alt":385,"src":386,":chart":16},"Weave 1 path, redrawn from motion, colored by speed","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fpath-05-weave-1.svg",[14,388],{"alt":389,"src":390,":chart":16},"Emergency braking 2 path, redrawn from motion, colored by speed","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fpath-06-emergency-braking-2.svg",[14,392],{"alt":393,"src":394,":chart":16},"Stop and go 1 path, redrawn from motion, colored by speed","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fpath-07-stop-and-go-1.svg",[14,396],{"alt":397,"src":398,":chart":16},"Slow ride 1 path, redrawn from motion, colored by speed","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fpath-08-slow-ride-1.svg",[14,400],{"alt":401,"src":402,":chart":16},"U turn from stop 2 path, redrawn from motion, colored by speed","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcharts\u002Fpath-09-u-turn-from-stop-2.svg",[217,404,406,410,413],{"eyebrow":405},"Blind recognition",[221,407,409],{"id":408},"_23-of-27-real-attempts-named-correctly","23 of 27 real attempts named correctly",[10,411,412],{},"The recognizer ran over the whole hour as one stream, without the marks, and was then scored against them. Four more runs held no drill at all: an aborted braking rep and three runs where Emergency Braking was tapped instead of Loosening Up. The shape check caught those.",[414,415,416,442],"table",{},[417,418,419],"thead",{},[420,421,422,426,430,433,436,439],"tr",{},[423,424,425],"th",{},"Marked run",[423,427,429],{"align":428},"right","Length",[423,431,432],{"align":428},"On-pattern",[423,434,435],{"align":428},"Reps",[423,437,438],{},"Recognizer says",[423,440,441],{},"Result",[443,444,445,466,485,502,519,536,555,573,592,611,630,649,667,686,703,720,738,756,773,791,807,824,842,858,874,891,908,924,940],"tbody",{},[420,446,447,451,454,457,460,463],{},[448,449,450],"td",{},"Slow ride #1",[448,452,453],{"align":428},"53 s",[448,455,456],{"align":428},"86%",[448,458,459],{"align":428},"1",[448,461,462],{},"Slow ride",[448,464,465],{},"match",[420,467,468,471,474,477,479,482],{},[448,469,470],{},"Slow ride #2",[448,472,473],{"align":428},"36 s",[448,475,476],{"align":428},"52%",[448,478,459],{"align":428},[448,480,481],{},"U turn from stop",[448,483,484],{},"miss",[420,486,487,490,493,496,498,500],{},[448,488,489],{},"Slow ride #3",[448,491,492],{"align":428},"38 s",[448,494,495],{"align":428},"66%",[448,497,459],{"align":428},[448,499,462],{},[448,501,465],{},[420,503,504,507,510,513,515,517],{},[448,505,506],{},"Slow ride #4",[448,508,509],{"align":428},"29 s",[448,511,512],{"align":428},"53%",[448,514,459],{"align":428},[448,516,462],{},[448,518,465],{},[420,520,521,524,527,530,532,534],{},[448,522,523],{},"Slow ride #5",[448,525,526],{"align":428},"34 s",[448,528,529],{"align":428},"59%",[448,531,459],{"align":428},[448,533,462],{},[448,535,465],{},[420,537,538,541,544,547,550,553],{},[448,539,540],{},"Stop and go #1",[448,542,543],{"align":428},"63 s",[448,545,546],{"align":428},"100%",[448,548,549],{"align":428},"6",[448,551,552],{},"Stop and go",[448,554,465],{},[420,556,557,560,563,566,569,571],{},[448,558,559],{},"Stop and go #2",[448,561,562],{"align":428},"64 s",[448,564,565],{"align":428},"88%",[448,567,568],{"align":428},"10",[448,570,552],{},[448,572,465],{},[420,574,575,578,581,584,587,590],{},[448,576,577],{},"Offset weave #2",[448,579,580],{"align":428},"124 s",[448,582,583],{"align":428},"84%",[448,585,586],{"align":428},"17",[448,588,589],{},"Offset weave",[448,591,465],{},[420,593,594,597,600,603,606,609],{},[448,595,596],{},"Weave #1",[448,598,599],{"align":428},"129 s",[448,601,602],{"align":428},"54%",[448,604,605],{"align":428},"23",[448,607,608],{},"Weave",[448,610,465],{},[420,612,613,616,619,622,625,628],{},[448,614,615],{},"Figure eight #4",[448,617,618],{"align":428},"70 s",[448,620,621],{"align":428},"0%",[448,623,624],{"align":428},"–",[448,626,627],{},"—",[448,629,484],{},[420,631,632,635,638,641,644,647],{},[448,633,634],{},"Figure eight #6",[448,636,637],{"align":428},"94 s",[448,639,640],{"align":428},"64%",[448,642,643],{"align":428},"5",[448,645,646],{},"Figure eight",[448,648,465],{},[420,650,651,654,657,660,663,665],{},[448,652,653],{},"Figure eight #7",[448,655,656],{"align":428},"206 s",[448,658,659],{"align":428},"78%",[448,661,662],{"align":428},"21",[448,664,646],{},[448,666,465],{},[420,668,669,672,675,678,681,684],{},[448,670,671],{},"Fixed circle #2",[448,673,674],{"align":428},"57 s",[448,676,677],{"align":428},"63%",[448,679,680],{"align":428},"3.1",[448,682,683],{},"Fixed circle",[448,685,465],{},[420,687,688,691,694,696,699,701],{},[448,689,690],{},"Fixed circle #3",[448,692,693],{"align":428},"45 s",[448,695,677],{"align":428},[448,697,698],{"align":428},"3.3",[448,700,683],{},[448,702,465],{},[420,704,705,708,710,713,716,718],{},[448,706,707],{},"Fixed circle #4",[448,709,674],{"align":428},[448,711,712],{"align":428},"68%",[448,714,715],{"align":428},"4.9",[448,717,683],{},[448,719,465],{},[420,721,722,725,728,731,733,736],{},[448,723,724],{},"Dual u turn #1",[448,726,727],{"align":428},"37 s",[448,729,730],{"align":428},"98%",[448,732,549],{"align":428},[448,734,735],{},"Dual u turn",[448,737,465],{},[420,739,740,743,746,749,752,754],{},[448,741,742],{},"Dual u turn #2",[448,744,745],{"align":428},"74 s",[448,747,748],{"align":428},"55%",[448,750,751],{"align":428},"12",[448,753,735],{},[448,755,465],{},[420,757,758,761,764,766,769,771],{},[448,759,760],{},"Dual u turn #3",[448,762,763],{"align":428},"131 s",[448,765,677],{"align":428},[448,767,768],{"align":428},"11",[448,770,735],{},[448,772,465],{},[420,774,775,778,781,784,786,789],{},[448,776,777],{},"Emergency braking #1",[448,779,780],{"align":428},"27 s",[448,782,783],{"align":428},"40%",[448,785,459],{"align":428},[448,787,788],{},"Emergency braking",[448,790,465],{},[420,792,793,796,798,800,803,805],{},[448,794,795],{},"Emergency braking #2",[448,797,509],{"align":428},[448,799,495],{"align":428},[448,801,802],{"align":428},"2",[448,804,788],{},[448,806,465],{},[420,808,809,812,815,818,820,822],{},[448,810,811],{},"Emergency braking #3",[448,813,814],{"align":428},"31 s",[448,816,817],{"align":428},"76%",[448,819,802],{"align":428},[448,821,788],{},[448,823,465],{},[420,825,826,829,832,835,837,839],{},[448,827,828],{},"Emergency braking #4",[448,830,831],{"align":428},"28 s",[448,833,834],{"align":428},"14%",[448,836,459],{"align":428},[448,838,683],{},[448,840,841],{},"no drill ridden",[420,843,844,847,850,852,854,856],{},[448,845,846],{},"Emergency braking #5",[448,848,849],{"align":428},"13 s",[448,851,546],{"align":428},[448,853,459],{"align":428},[448,855,788],{},[448,857,465],{},[420,859,860,863,865,868,870,872],{},[448,861,862],{},"Emergency braking #6",[448,864,831],{"align":428},[448,866,867],{"align":428},"49%",[448,869,802],{"align":428},[448,871,788],{},[448,873,465],{},[420,875,876,879,882,885,887,889],{},[448,877,878],{},"U turn from stop #1",[448,880,881],{"align":428},"33 s",[448,883,884],{"align":428},"32%",[448,886,459],{"align":428},[448,888,735],{},[448,890,484],{},[420,892,893,896,899,901,904,906],{},[448,894,895],{},"U turn from stop #2",[448,897,898],{"align":428},"147 s",[448,900,476],{"align":428},[448,902,903],{"align":428},"7",[448,905,481],{},[448,907,465],{},[420,909,910,913,916,918,920,922],{},[448,911,912],{},"Emergency braking #7",[448,914,915],{"align":428},"130 s",[448,917,621],{"align":428},[448,919,624],{"align":428},[448,921,627],{},[448,923,841],{},[420,925,926,929,932,934,936,938],{},[448,927,928],{},"Emergency braking #8",[448,930,931],{"align":428},"103 s",[448,933,621],{"align":428},[448,935,624],{"align":428},[448,937,627],{},[448,939,841],{},[420,941,942,945,948,950,952,954],{},[448,943,944],{},"Emergency braking #9",[448,946,947],{"align":428},"50 s",[448,949,621],{"align":428},[448,951,624],{"align":428},[448,953,683],{},[448,955,841],{},[217,957,959,963,966],{"eyebrow":958},"The whole hour",[221,960,962],{"id":961},"marks-above-shapes-below","Marks above, shapes below",[10,964,965],{},"Ten-minute strips. Gray is speed, blue is turn rate. The top band is what was marked in the app; the bottom band is what the shape recognizer found by itself, including practice nobody marked.",[14,967],{"alt":968,"src":969,":wide":16},"Timeline of the drill session in ten-minute strips with marked runs and detected drills","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Ftimeline.webp",[217,971,973,976,979,984,988],{"eyebrow":972},"Coaching numbers",[221,974,3],{"id":975},"right-turns-lean-further",[10,977,978],{},"Same radius, same speed, and yet the right side leans 2–6° more in every turning drill. The physics asks for the same lean both ways, so this is the rider, and it's the kind of thing an app can point out: ride more of the harder side.",[14,980,981],{"alt":17,"src":18,":chart":16,":wide":16},[10,982,983],{},"Median peak lean per turn, left (blue) and right (orange). The labels give each side's median radius and the number of turns.",[985,986,788],"h3",{"id":987},"emergency-braking",[188,989,990,997],{},[191,991,992],{},[14,993,994],{"alt":70,"src":71,":chart":16},[10,995,996],{},"Stopping distance from brake onset, with entry speed. Peak deceleration is averaged over 0.5 s because the stick-mounted camera exaggerates the instant peak.",[191,998,999,1002],{},[10,1000,1001],{},"The brakes come on hard and fast: 80% of peak within 0.2–0.3 s every time. The last few mph are then shed gently, so the average over the whole stop is only about half the peak.",[10,1003,1004],{},"On the road, eleven ordinary traffic stops peaked at 0.14–0.34 g. The lot stops reached 0.73–0.82 g. The difference between an everyday stop and an emergency one is exactly what the drill trains, and it shows up in one number.",[217,1006,1008,1012],{"eyebrow":1007},"Street riding",[221,1009,1011],{"id":1010},"the-bike-settles-as-speed-rises","The bike settles as speed rises",[188,1013,1014,1077],{},[191,1015,1016],{},[414,1017,1018,1031],{},[417,1019,1020],{},[420,1021,1022,1025,1028],{},[423,1023,1024],{},"Speed",[423,1026,1027],{"align":428},"Steering corrections, 1.5–4 Hz",[423,1029,1030],{"align":428},"Wobble band, 5–10 Hz",[443,1032,1033,1044,1055,1066],{},[420,1034,1035,1038,1041],{},[448,1036,1037],{},"2–6 mph",[448,1039,1040],{"align":428},"9.8 °\u002Fs",[448,1042,1043],{"align":428},"1.4 °\u002Fs",[420,1045,1046,1049,1052],{},[448,1047,1048],{},"10–15 mph",[448,1050,1051],{"align":428},"1.9 °\u002Fs",[448,1053,1054],{"align":428},"2.0 °\u002Fs",[420,1056,1057,1060,1063],{},[448,1058,1059],{},"20–25 mph",[448,1061,1062],{"align":428},"1.1 °\u002Fs",[448,1064,1065],{"align":428},"1.7 °\u002Fs",[420,1067,1068,1071,1074],{},[448,1069,1070],{},"25–30 mph",[448,1072,1073],{"align":428},"1.0 °\u002Fs",[448,1075,1076],{"align":428},"1.6 °\u002Fs",[191,1078,1079,1082],{},[10,1080,1081],{},"Handlebar corrections fall tenfold from walking pace to 25 mph, as the bike becomes self-stable. Nothing grows in the wobble band. Slow riding is where the work is, which is why the drills are slow.",[200,1083,1084],{},[10,1085,1086],{},"From the phone on the ride home: 46.5 mph top speed, six minutes above 20 mph.",[217,1088,1090,1094],{"eyebrow":1089},"Next",[221,1091,1093],{"id":1092},"what-would-sharpen-this","What would sharpen this",[261,1095,1096,1099,1102,1105],{},[264,1097,1098],{},"A road ride with 20+ turn-ins above 20 mph, with the Action 6 on the bars and the X5 on the frame, to fill in the highway row of the steering chart.",[264,1100,1101],{},"A glance at Sensor Logger two minutes into every session, and a restart if its plots are frozen.",[264,1103,1104],{},"Drill templates drawn from the real shapes, so size can be scored against the size each rider picks.",[264,1106,1107],{},"For the app: a second, frame-fixed sensor makes countersteer and lean coachable from phones alone.",[217,1109,1111,1115,1122,1129,1136],{"eyebrow":1110},"Working figures",[221,1112,1114],{"id":1113},"from-the-analysis-notebook","From the analysis notebook",[14,1116,1119],{"alt":1117,"src":1118,":wide":16},"One panel per run showing the dead-reckoned path","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fruns_grid.webp",[10,1120,1121],{},"Every marked run, drawn from the frame camera over the raw GPS fixes (gray).",[14,1123,1126],{"alt":1124,"src":1125,":wide":16},"Steering ensembles by speed band","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fsteer_countersteer.webp",[10,1127,1128],{},"The steering result as produced by the analysis script.",[14,1130,1133],{"alt":1131,"src":1132,":wide":16},"Frame motion at turn-in during drills","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fcountersteer_drills.webp",[10,1134,1135],{},"The earlier, frame-only test: roll leads yaw at turn-in in 46 of 53 drill turns.",[188,1137,1138,1147],{},[191,1139,1140],{},[14,1141,1144],{"alt":1142,"src":1143},"Gyro spectrum of the stick-mounted camera","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fx5_spectrum.webp",[10,1145,1146],{},"Selfie-stick shake sits near 42 Hz; riding lives below 5 Hz.",[191,1148,1149],{},[14,1150,1153],{"alt":1151,"src":1152},"Handlebar rate spectrum on the street","\u002Ffield-notes\u002F2026-09-29-countersteer\u002Fstreet_spectrum.webp",[10,1154,1155],{},"Handlebar rate spectrum on the ride home.",{"title":44,"searchDepth":45,"depth":45,"links":1157},[1158,1159,1160,1161,1162,1163,1164,1168,1169,1170],{"id":223,"depth":45,"text":224},{"id":240,"depth":45,"text":241},{"id":325,"depth":45,"text":326},{"id":353,"depth":45,"text":354},{"id":408,"depth":45,"text":409},{"id":961,"depth":45,"text":962},{"id":975,"depth":45,"text":3,"children":1165},[1166],{"id":987,"depth":1167,"text":788},3,{"id":1010,"depth":45,"text":1011},{"id":1092,"depth":45,"text":1093},{"id":1113,"depth":45,"text":1114},"2026-09-29","A handlebar camera and a frame camera recorded together. Subtract one from the other and the rider's steering is what remains. At turn-in the bars go the wrong way first.",{},"\u002Ffield-notes\u002F2026-09-29-countersteer",{"title":41,"description":1172},"field-notes\u002F2026-09-29-countersteer","U35Llzcjp0NMIcrpi66P9TLKNogIlSL6A91mk9YmSDU","fieldNote",{"id":1180,"title":1181,"body":1182,"date":1569,"description":1570,"draft":49,"extension":50,"image":1198,"imageAlt":1571,"kicker":1572,"meta":1573,"navigation":54,"path":1574,"pinned":54,"seo":1575,"stem":1576,"__hash__":1577,"kind":1178},"fieldNotes\u002Ffield-notes\u002F2026-09-07-the-miracle-happened.md","The Miracle Happened!",{"type":7,"value":1183,"toc":1559},[1184,1192,1195,1202,1218,1268,1320,1372,1486,1504,1545],[10,1185,1186,1187,1191],{},"The ",[38,1188,1190],{"href":1189},"\u002Fabout\u002F","About page"," ends with a phone on the handlebars, some raw data\nhanded to a Claude Code AI session, and a request for a miracle.",[10,1193,1194],{},"This is what happened next.",[14,1196,1199],{"alt":1197,"src":1198},"GPS position fixes for the 21-minute session, a scattered cloud of dots","\u002Ffield-notes\u002F2026-09-07-the-miracle-happened\u002Fgps-fixes.webp",[10,1200,1201],{},"Twenty-one minutes of drills, as the phone's GPS saw them. There are drills in there. How they came out is below.",[217,1203,1204,1208,1211],{},[221,1205,1207],{"id":1206},"twenty-one-minutes-of-numbers","Twenty-one minutes of numbers",[10,1209,1210],{},"The input wasn't much to look at. It was one zip file from an app called Sensor Logger, recorded during\n21 minutes and 35 seconds of parking-lot drills, plus a short clip recorded in the garage. It had no\nvideo, no notes about which drill was which, and no cones. It held a few million rows of numbers from\nthe phone's accelerometer, gyroscope, compass and GPS, and that was all.",[10,1212,1213,1214],{},"The one instruction was roughly this: ",[1215,1216,1217],"em",{},"here's the data, I tapped the phone to mark my drills, see what\nyou can find.",[217,1219,1220,1224,1227,1230,1237,1244,1262,1265],{},[221,1221,1223],{"id":1222},"the-obvious-answer-was-a-blob","The obvious answer was a blob",[10,1225,1226],{},"The natural first move is to plot the GPS track. Phones know where they are, so the drills should\njust appear.",[10,1228,1229],{},"They didn't. The GPS dots made a featureless smear across the lot. The phone's position was only good to\nabout 4 meters (12 feet), and the drills themselves are only 6–12 meters across. Asking GPS to draw a\nfigure eight is like signing your name with a paint roller.",[10,1231,1232,1233,1236],{},"Claude noticed one thing hiding in the same data, though. The GPS ",[78,1234,1235],{},"speed"," was excellent, good to\nabout a sixth of a mile per hour. Speed comes from the Doppler shift of the satellite signals, not from\nposition, so it doesn't share position's blur.",[10,1238,1239,1240,1243],{},"That became the key idea: ",[78,1241,1242],{},"let the gyroscope draw the shape, and let GPS supply the speed."," The gyro\nknows exactly how the bike is turning, moment by moment. GPS knows exactly how fast it's moving.\nCombine the two and walk forward one two-hundredth of a second at a time. Navigators call it dead\nreckoning: no map, just \"which way am I pointed, how fast am I going, and for how long.\"",[188,1245,1246,1253],{},[191,1247,1248],{},[14,1249,1250],{"alt":1197,"src":1198},[10,1251,1252],{},"What GPS saw: every position fix from the 21 minutes, colored by time.",[191,1254,1255],{},[14,1256,1259],{"alt":1257,"src":1258},"The same 21 minutes drawn from the gyroscope and GPS speed, overlapping loops and figure eights","\u002Ffield-notes\u002F2026-09-07-the-miracle-happened\u002Fdead-reckoned.webp",[10,1260,1261],{},"The same 21 minutes, drawn from the gyroscope with GPS speed for scale.",[10,1263,1264],{},"The same session, the same 21 minutes. On the left is what GPS sees. On the right is what the phone's\nown sensors drew: rounded rectangles, serpentines, figure eights and tight circles, all overlapping\nwhere they were ridden in the same corner of the lot.",[10,1266,1267],{},"That was the moment.",[217,1269,1270,1274,1277,1280,1283,1297,1304,1307,1314,1317],{},[221,1271,1273],{"id":1272},"finding-the-taps-in-a-running-engine","Finding the taps in a running engine",[10,1275,1276],{},"Rich had marked his drills by tapping the phone: three taps to start, two between reps, four to end.\nThat's easy to see in a quiet room and hard to see on an idling 1100 cc twin.",[10,1278,1279],{},"The first attempt failed. The obvious method listens for sharp, high-pitched jolts, and the engine\nfloods exactly that range. Filtering harder didn't help, because the engine is loud at every pitch the\nfilter could pick.",[10,1281,1282],{},"So Claude asked what makes a fingertip different from an engine, and found two answers:",[261,1284,1285,1291],{},[264,1286,1287,1290],{},[78,1288,1289],{},"A tap is sudden."," It's over in a few milliseconds.",[264,1292,1293,1296],{},[78,1294,1295],{},"A tap twists the phone."," A finger lands off-center, so the gyroscope feels a small rotation. Engine\nvibration mostly shakes the phone back and forth without twisting it.",[10,1298,1299,1300,1303],{},"A real tap has to show up in ",[78,1301,1302],{},"both"," sensors at the same instant. That rule cut through the engine\nnoise.",[10,1305,1306],{},"To test it, Claude used the short garage clip, recorded with the engine off. Rich had tapped three\ntimes before each flip and shake of the phone. The detector found every one of those triple-taps, about\nthree-tenths of a second apart. It had learned Rich's rhythm.",[14,1308,1311],{"alt":1309,"src":1310},"The garage calibration: four triple-taps (red lines) ahead of each flip and shake","\u002Ffield-notes\u002F2026-09-07-the-miracle-happened\u002Fcal.webp",[10,1312,1313],{},"The garage calibration: four triple-taps (red lines) ahead of each flip and shake.",[10,1315,1316],{},"Then came the real test. With no list of drills to go on, the detector found a three-tap, four\naccelerate-and-stop runs separated by two-taps, and a closing four-tap. It had worked out the\nemergency-braking drill and the marking scheme from the signal alone.",[10,1318,1319],{},"It also found taps while the bike was rolling at 8–10 mph, with spacing so even that the analysis\nnotes called it \"a metronome, not a pothole.\" So the app shouldn't assume a rider stops before marking.",[217,1321,1322,1326,1329,1336,1339,1366,1369],{},[221,1323,1325],{"id":1324},"every-drill-drawn","Every drill, drawn",[10,1327,1328],{},"With the taps found, the ride split into segments, and Claude drew each one.",[14,1330,1333],{"alt":1331,"src":1332,":wide":16},"Every tap-delimited segment, green dot start, red square end","\u002Ffield-notes\u002F2026-09-07-the-miracle-happened\u002Fshapes-segments.webp",[10,1334,1335],{},"Every tap-delimited segment, green dot start, red square end.",[10,1337,1338],{},"Claude learned to read them without being told what they were:",[261,1340,1341,1348,1354,1360],{},[264,1342,1343,1344,1347],{},"A ",[78,1345,1346],{},"circle"," turns a full 360° every lap.",[264,1349,1343,1350,1353],{},[78,1351,1352],{},"figure eight"," turns plenty but ends up facing about where it started.",[264,1355,1343,1356,1359],{},[78,1357,1358],{},"U-turn"," turns 180°.",[264,1361,1343,1362,1365],{},[78,1363,1364],{},"stop-and-go"," run has a stop every few seconds.",[10,1367,1368],{},"One segment came out as four neat lobes, which matched Rich's description of the offset weave. Another\nturned 1,169° in 46 seconds, which is about three and a quarter tight circles. Two long stretches had no\ntaps at all, but the drawings showed real drills in both. Some taps had simply been missed, which turned\ninto a lesson for the app: marking has to be easy, or it won't get done.",[10,1370,1371],{},"Claude got one guess wrong. It expected a long pause where Rich had stopped to fiddle with a camera, and\nthe data said there was no such pause in this file. Claude reported that plainly instead of bending the\ndata to fit the story.",[217,1373,1374,1378,1381,1456,1463,1469,1472,1479],{},[221,1375,1377],{"id":1376},"the-braking-numbers-held-up","The braking numbers held up",[10,1379,1380],{},"The emergency-braking reps produced real coaching numbers: speed at the brake, stopping distance, and\nhow hard the bike slowed.",[414,1382,1383,1399],{},[417,1384,1385],{},[420,1386,1387,1390,1393,1396],{},[423,1388,1389],{},"Rep",[423,1391,1392],{},"Speed at braking",[423,1394,1395],{},"Distance to stop",[423,1397,1398],{},"Peak slowing",[443,1400,1401,1414,1427,1440],{},[420,1402,1403,1405,1408,1411],{},[448,1404,459],{},[448,1406,1407],{},"23 mph",[448,1409,1410],{},"40 ft",[448,1412,1413],{},"0.79 g",[420,1415,1416,1418,1421,1424],{},[448,1417,802],{},[448,1419,1420],{},"28 mph",[448,1422,1423],{},"56 ft",[448,1425,1426],{},"0.91 g",[420,1428,1429,1432,1434,1437],{},[448,1430,1431],{},"3",[448,1433,1420],{},[448,1435,1436],{},"63 ft",[448,1438,1439],{},"0.88 g",[420,1441,1442,1445,1448,1451],{},[448,1443,1444],{},"4",[448,1446,1447],{},"32 mph",[448,1449,1450],{},"50 ft",[448,1452,1453],{},[78,1454,1455],{},"1.00 g",[14,1457,1460],{"alt":1458,"src":1459,":wide":16},"Top: speed, with GPS dots and the blended line; bottom: braking force","\u002Ffield-notes\u002F2026-09-07-the-miracle-happened\u002Fbraking.webp",[10,1461,1462],{},"Top: speed, with GPS dots and the blended line; bottom: braking force.",[10,1464,1465,1466],{},"Rich looked at those distances and pushed back: ",[1215,1467,1468],{},"are these twice too long?",[10,1470,1471],{},"That was the right question to ask, and the answer wasn't \"trust me.\" Claude measured the distance again\ntwo more ways that share no code with the first: once from the raw GPS speed, and once from the GPS\nposition. The raw-speed figure agreed within 2–7%. The position figure came out a little short, and the\nreason is known: phones smooth their position, so it lags during a hard stop. The distances were real.",[10,1473,1474,1475,1478],{},"The interesting part was ",[78,1476,1477],{},"why"," they were long. On every rep the brakes reached their peak, but late.\nAverage slowing was only about half of peak, because the distance was lost while the brake pressure was\nstill building, not at the peak. Reps 2 and 3 started at the same speed but stopped 7 feet apart. Rep 4,\nthe fastest, scaled down to 20 mph, would have passed a common 25-foot standard with room to spare. One\ngenuinely good stop and three that weren't is far more useful to a rider than an average.",[10,1480,1481,1482,1485],{},"Then came an unexpected idea: entry speeds varied by 9 mph from rep to rep. Since stopping distance grows\nwith the ",[78,1483,1484],{},"square"," of speed, that one inconsistency could almost double the stopping distance before\ntechnique even enters into it. A beep at the target speed would fix most of that, and the numbers say\neven a slow beep would do.",[217,1487,1488,1492,1499],{},[221,1489,1491],{"id":1490},"what-it-couldnt-find-and-what-that-led-to","What it couldn't find, and what that led to",[10,1493,1494,1495,1498],{},"Not everything worked. Claude searched hard for ",[78,1496,1497],{},"countersteering",", the brief push of the bars away\nfrom the turn that starts every lean. It didn't find it. Rather than claim a result, it worked out why:\nin 21 minutes of slow drills, the bike was turning above 20 mph for less than one second. The experiment\nsimply hadn't asked the question.",[10,1500,1501,1502,42],{},"Three weeks later, with a camera on the frame and another on the bars, it did. That story is in\n",[38,1503,41],{"href":40},[217,1505,1506,1510,1513,1539,1542],{},[221,1507,1509],{"id":1508},"so-was-it-a-miracle","So, was it a miracle?",[10,1511,1512],{},"No magic was involved. A phone on the handlebars, one ordinary practice session, and an AI that:",[261,1514,1515,1521,1527,1533],{},[264,1516,1517,1520],{},[78,1518,1519],{},"tried the obvious thing first"," and said so when it failed,",[264,1522,1523,1526],{},[78,1524,1525],{},"looked for a second way in",": gyroscope for shape, GPS for speed, a twist for a tap,",[264,1528,1529,1532],{},[78,1530,1531],{},"checked its own work"," against a quiet garage, a known drill, and three independent measurements,",[264,1534,1535,1538],{},[78,1536,1537],{},"reported what it couldn't find"," as clearly as what it could.",[10,1540,1541],{},"By the end of the day, a pocket phone had drawn every drill, found every marked brake rep, scored them,\nand pointed to the habit that was costing stopping distance.",[10,1543,1544],{},"For a rider who practices without cones, that's close enough to a miracle. It's also why MotoDrill\nexists.",[217,1546,1547,1551,1554],{},[221,1548,1550],{"id":1549},"whats-next","What's next",[10,1552,1553],{},"Rich's next ride brought new challenges. He now had an app that clearly marked each drill, but the phone's sensor logger stopped running. A totally wasted ride? No. Claude Code pulled another rabbit out of a hat. This time a 360 hat.",[10,1555,1556],{},[38,1557,1558],{"href":40},"Countersteer, caught on two cameras →",{"title":44,"searchDepth":45,"depth":45,"links":1560},[1561,1562,1563,1564,1565,1566,1567,1568],{"id":1206,"depth":45,"text":1207},{"id":1222,"depth":45,"text":1223},{"id":1272,"depth":45,"text":1273},{"id":1324,"depth":45,"text":1325},{"id":1376,"depth":45,"text":1377},{"id":1490,"depth":45,"text":1491},{"id":1508,"depth":45,"text":1509},{"id":1549,"depth":45,"text":1550},"2026-09-07","One phone on the handlebars, 21 minutes of raw sensor data, and no list of drills. Claude Code drew every drill, found every brake rep and scored them.","The phone's GPS position fixes for the session, a scattered cloud of dots that shows no drills","Field session · 7 Sep 2026 · an empty parking lot · Honda Rebel 1100 DCT",{},"\u002Ffield-notes\u002F2026-09-07-the-miracle-happened",{"title":1181,"description":1570},"field-notes\u002F2026-09-07-the-miracle-happened","ut_VKNQI10xNvnK_zS2WT0BdT6xBDMPdpzYFmbspS6Y",1791483522446]