• First-time users should read Chapter 1 (Know Your Product) and Chapter 2 (Quick Start) first — you’ll be recording in 5 minutes.
• To dig into a feature, jump straight to its chapter; every screen page uses the same format: When / how to enter → Display → Buttons → Exit.

Read this chapter carefully before use. Using this product means you understand and agree to the following.

1. Operating safety. Switching menus, confirming settings, checking data and similar actions should be done while the vehicle is stopped; do not operate the watch while moving, to avoid distraction. Start and end sessions before setting off and after coming to a stop.
2. Nature of the data. The speed, lap times, acceleration and G-force recorded by this watch are for personal practice and reference only; derived from satellite positioning (GPS/GNSS) and built-in sensors, they are not officially certified timing or speed equipment, and must not be used as a basis for competition results, insurance claims, legal disputes or any other official purpose.
3. Positioning accuracy. GPS/GNSS accuracy is affected by weather, terrain, buildings, tunnels and other conditions, so data may contain errors — especially in mountains, underground car parks and dense urban areas.
4. Venues & legal compliance. When performing acceleration, lap-time or off-road tests, always obey local traffic laws and speed limits, and only on legal circuits, closed venues or private property. If speed or acceleration testing on public roads breaks traffic laws, the user bears full responsibility; the manufacturer accepts no legal liability.
5. Off-road use. In Off-Road mode, ensure the safety of the vehicle, route and yourself, and wear appropriate protective gear. The watch’s attitude/tilt data is for reference only and is no guarantee of vehicle stability or safety.
6. Charging & battery. Charge only with the original or specified charging clip/adapter; avoid charging in heat, humidity or near flammable materials; if unused for long periods, charge periodically to keep the battery healthy.
7. General disclaimer. Damage or data anomalies caused by improper use, failing to follow this manual, unauthorized disassembly, or non-original accessories (such as unofficial RaceBox-compatible devices) are not covered by warranty.

The STINT GTM is a GPS Racing Watch built for driving and track enthusiasts. It records your acceleration, lap times, mountain-road and off-road performance and saves each session’s track, speed and G-force (lateral / accel-brake) in full for later review on the watch, mobile app or computer. Day to day it is also an everyday watch with time, alarm, compass, barometer and heart rate.

The watch has a 240 × 240 full-color screen, four physical buttons and a backlight button that doubles as LAP during sessions.

Button basics: most actions are a short press (press and release). A few need a long press; how long depends on the function (e.g. backlight ~1 s, ending a session ~2 s, power off ~5 s), and this manual clearly notes it.

Sessions can use three positioning sources, freely switchable in Settings:

Just got your watch? Follow these steps to make your first recording.

1. Charge & power on　Clip the supplied charging clip onto the watch body and charge it fully (while charging, the watch is in charging mode and cannot be operated). After you unplug the charger it powers on automatically, briefly showing the boot screen before the watch face.
2. Set time & basics (face → OK → SETUP → System Settings)
   • Time: go to Time → Set Time and choose GPS SYNC, then go to an open outdoor area and wait for a fix — the time sets automatically. With no GPS signal you can also use MANUAL SET (see 10.2).
   • Language: English / Traditional Chinese / Simplified Chinese.
   • Units: metric or imperial for everyday display. (Racing speed units are set separately in Racing settings.)
3. Choose a GPS source (SETUP → SET GPS)
   Start simplest: choose INTERNAL GPS — no pairing needed.
4. Record your first session (face → OK → RACING)
   The watch searches for a fix → choose DAILY DRIVE → when the GPS dot turns green press OK to start → to finish hold BACK ~2 s; the screen shows Saving... and the session is saved.
5. Review it　Back at the watch face, press DOWN for the Racing overview — top speed, distance and more. For per-session detail go to face OK → RECORDS.

Done! The following chapters explain each screen one by one.

The watch has several switchable faces (see 10.2 System Settings to switch). Whichever you choose, the buttons work the same; which information appears depends on the face (see 4.4). This chapter covers the common operations and uses the classic faces as the example in 4.1.

• Battery gauge (top)
• Weekday & date
• Time (in 12-hour mode Classic Digital shows AM/PM; switchable to 24-hour in Settings)
• Racing signature line: a snapshot of your sessions — with no records it shows NO RACE YET; with records it shows SPD (top speed) and SESS (sessions). It always covers only the newest 10 records in RECORDS (TILT records among them are not counted as sessions), so the session count is 10 at most; speed follows SETUP → RACING → SPEED UNIT and no unit is shown on screen.
• App connection icon: while the mobile app is connected, a white Bluetooth symbol appears to the right of the battery gauge (see 11.4).

Face → TILT (FreeTilt) → Compass → (HR monitor*) → Barometer → HR info → back to face

• On each page: UP forward, DOWN back, BACK to the face. Two exceptions: BACK on the compass returns to TILT first (press BACK again for the face); with the HR monitor enabled, DOWN on the barometer goes straight back to the compass.
• Compass: when calibration is needed it opens the calibration screen automatically; just rotate the watch as prompted.

Heart-rate monitor (*): appears only after System Settings → Heart Rate → HR Monitoring is enabled; shows a 4-hour heart-rate bar chart and live heart rate, returning to the face after ~60 s of inactivity.

The watch ships with 8 watch faces in three groups: 2 Classic (the previous look), 4 Achievement (your cumulative results shown right on the face, see 4.6) and 2 Minimal (time and battery only). In the settings preview, achievement faces are labelled with the name shown in brackets (see “How to switch” below).

How to switch: main menu → SETUP → System Settings → Watch face (see 10.2). Inside, UP/DOWN steps through the previews (the preview is the real appearance; before you have any achievement data, an achievement face’s preview shows its name in the centre, e.g. OVERVIEW, instead of READY TO RACE), OK saves and applies, BACK discards. The list does not wrap — pressing UP on the first face or DOWN on the last will not jump to the other end.

FreeTilt is a GPS-free quick tilt tool: clamp the watch to a roll cage or dashboard at any angle, zero it once, and from then on you can see how far the vehicle is tilted relative to level — useful for levelling when parked and for judging slopes. Unlike ordinary inclinometers, you do not have to align the mount (Mount & Go).

• Entering: press UP from the watch face; FreeTilt is the first stop in the carousel (see 4.3).
• First use: the screen shows PARK LEVEL / PRESS OK TO ZERO — park on level ground and press OK to zero (it shows HOLD STILL while collecting, so stay still; if it cannot stay still for about 3 seconds in a row within about 10 seconds — for example because the vehicle rocks or the engine vibrates — it shows NOT LEVEL / RETRY; press any button to clear it, then press OK to try again).
• After zeroing: the artificial horizon shows roll (R) and pitch (P) live, with the age of the reference below (e.g. ZERO 5m). The reference is kept, so you only need to re-zero when you change mounts or the way it is fixed — when not recording, hold BACK for 1 second (the hint BACK 1S: ZERO is shown at the bottom). Let go once the second has passed: holding for about 5 seconds powers the watch off.
• Recording: press OK to start (a red dot appears, 25 Hz sampling); press OK again to stop and save (it shows SAVED and the sample count). The recording appears in RECORDS marked TILT. It stops and saves automatically below about 3.5 V or after 2 hours. After you press OK it may show STARTING for a few seconds; buttons are ignored during that time and for about 1 second after recording starts, so a double press can’t stop it straight away. With records full or not enough space it shows STORAGE FULL / DELETE OLD LOGS and won’t start (delete a few old records, see 9.3). If the battery is already below about 3.5 V, pressing OK shows LOW BATTERY / CHARGE TO REC — charge it first. When recording stops because of low battery, LOW BATT appears under SAVED.
• Other messages: SAVE FAILED = that recording was not saved; the watch stays on this page so you can see it — check free space and battery, then record again (see Chapter 12). STORAGE ERROR = a read/write error (not a full memory, so deleting records won’t fix it). NO IMU = no attitude data for about 3 seconds; the horizon returns once the data comes back. STORAGE FULL, STORAGE ERROR, LOW BATTERY and NOT LEVEL clear with any button (that press does not trigger the button’s normal action); SAVED and SAVE FAILED disappear after about 2 seconds.
• Leaving: UP goes to the compass, DOWN/BACK returns to the face; leaving while recording saves first.
• Afterwards: recordings can sync to the mobile app, which can overlay the attitude onto your driving video (see 11.14).

Achievement faces (see 4.4) show two lifetime figures — lifetime distance and drives — plus today’s top speed. The lifetime figures are not limited to the last 10 sessions — deleting one record or all records in RECORDS keeps the totals (for the clearing options in SETUP, see 10.6).

• Distance units follow SETUP → RACING → SPEED UNIT (km/h shows KM, mph shows MI) and do not follow the metric/imperial system setting.
• Large numbers are abbreviated: below 10,000 the full number is shown; from 10,000 it uses K and from 1,000,000 it uses M, with one decimal place (truncated, and a trailing .0 is dropped: 12,000 shows 12K, 12,345 shows 12.3K). The Odometer face’s digit boxes show all 6 digits up to 999,999.
• With no records yet, achievement faces show READY TO RACE and 0 KM | 0 DRIVES rather than a meaningless 0 as the headline figure.
• When it counts: a drive must have at least one segment saved successfully to be added. If you pressed start but it failed or lost power before the first segment was saved, it does not count.

The Milestone face shows how far you are from your next target. The steps are:

100 → 250 → 500 → 1,000 → 2,500 → 5,000 → 10,000 → every 5,000 after that

After you cross a milestone, the next time you return to that face (for example from the main menu or the info pages) it shows a MILESTONE! congratulation once, then switches to the progress toward the next target. Switching between KM and MI does not trigger a false congratulation.

Press OK at the watch face to open the main menu. It has 3 items and shows one at a time; UP/DOWN cycle, OK enters, BACK returns to the face (the dots at the bottom show which item you are on).

This is the heart of the watch. A complete Racing flow is:

Menu RACING → connect / find sats → pick mode → (DRAG: pick method / LAP TIMER: pick lap mode) → standby → start recording (Live)

This section clears up the logic and terms most often misunderstood. Two minutes here saves a lot of trouble.

• DAILY DRIVE: records continuously from start to manual save, with no splits or laps — just distance, average speed and top speed.
• DRAG: measures acceleration, in three methods (below) that you choose.
• LAP TIMER: circuit lap times — counted by button press with BUTTON (above), or automatically from a start/finish line with GPS AUTO (see Chapter 7).
• TOUGE: free mountain-road runs, no laps — records total distance, average and top speed, peak G-force and elevation gain; for continuous driving rather than lap comparison.
• OFF-ROAD: measures vehicle attitude (roll and pitch), not speed or acceleration. Needs MOUNT=VEHICLE Tilt first needs MOUNT set to VEHICLE with the watch fixed to the vehicle. The Live artificial horizon always uses the watch’s own IMU, so it works with all three sources, but it needs a moment standing still to capture its reference (see 6.6). Tilt on the detail page afterward also needs a source that records true three-axis acceleration: built-in GPS records the watch’s IMU and a RaceBox its own IMU, but Qstarz records no acceleration, so Qstarz sessions have no tilt in the detail. When the conditions aren’t met, the detail’s attitude page shows NO TILT / NEEDS VEHICLE MOUNT (see 6.6).

• STANDING: launch from a complete stop, measuring split acceleration times (e.g. 0–100 km/h).
• QUARTER MILE: elapsed time and trap speed over a fixed 1/4-mile distance.
• ROLLING: starts while already moving; press OK for a 3-2-1 countdown, timing begins at “GO.” Lifting off ends the run automatically (detected when speed drops from its peak for about half a second) — no manual stop needed.

In the detail page, green (best) marks the shortest of all completed laps in that session; orange (slowest) marks the longest — not the first or last lap. The GPS AUTO warm-up and an unfinished final part-lap at save time are left out, and laps flagged for problems such as lost GPS are never picked as best.

Actual density = min(your set sample rate, the source’s real update rate). Built-in GPS and Qstarz have a far lower ceiling than an external RaceBox, so raising the sample rate does not truly refine the data — this isn’t a failed setting or a fault.

Switching source in SET GPS (between RACEBOX / INTERNAL GPS / QSTARZ) saves immediately, but takes effect only the next time you enter Racing; the current session keeps the source locked in at its start, and changing it in the app mid-session has no effect.

When a session fills up (depending on the actual sample rate: about 45 minutes at 25 Hz, 1.9 hours at 10 Hz, 3.75 hours at 5 Hz), the watch saves automatically and carries on in a new session: Saving... shows briefly with one long beep, and the timer and distance reset while the lap count carries on. Nothing else tells you a new session has begun; if a recording seems shorter than expected, this is why. MAX REC (see 6.4, Step 5) counts the whole run: even though the on-screen timer resets after a split, the automatic end still goes by the total time. Because MAX REC is at most 4 hours, at an actual sample rate of 2 Hz or less (including DAILY DRIVE, fixed at 1 Hz) a session never fills before it ends, so it is never split.

Most screens follow RACING → SPEED UNIT (km/h ↔ mph), but these stay fixed in km/h and do not convert: speed on the LAP TIMER detail page, and the QUARTER MILE split thresholds (0–60 / 0–100 / 0–160 km/h; the 0-100 KM/H on the DRAG dial layout too). STANDING, by contrast, switches to mph thresholds with the unit (see 6.6).

• RaceBox Mini: no pairing — switch it on nearby, set the source to RACEBOX, and it connects automatically when you enter Racing (next section); most complete data.
• Built-in GPS: no pairing, ready to use.
• Qstarz logger: no pairing — switch the Qstarz device (BL-1000GT / 818GT) on nearby, set the source to QSTARZ, and it connects automatically when you enter Racing.

The RaceBox Mini does not need pairing — when the watch enters Racing it searches for a nearby RaceBox and connects to whatever it finds.

1. Switch on the RaceBox Mini and put it in the vehicle (make sure it is charged).
2. Set the watch’s GPS source to RACEBOX (see 10.1).
3. Enter Racing; the watch shows Connect to GPS Devices... and connects automatically, then goes straight to the mode list.

From the main menu choose RACING; the watch prepares according to your GPS source:

• RaceBox / Qstarz: shows Connect to GPS Devices... and the current connection stage with elapsed seconds (e.g. Scanning 12s); once connected it opens the mode list automatically.
• Built-in GPS: shows GPS Searching... and fix progress (percent, signal, satellite count); once a fix is obtained it opens the mode list automatically.
• Pressing BACK here returns to the main menu (and drops the connection).
• If no signal is found: after about 5 minutes (external sources — RaceBox / Qstarz) or 20 minutes (built-in GPS) it reports not found and returns to the watch face.

In the mode list use UP/DOWN to choose and OK to select. If you pick DRAG, next choose a method (see 6.6); if you pick LAP TIMER, next choose the lap mode, BUTTON (manual) or GPS AUTO (automatic, see Chapter 7). BACK drops the connection and returns to the main menu. If the mode list or the DRAG method screen sits for 5 minutes with no button pressed, the watch returns to the face.

The standby screen shows the mode name (abbreviated, e.g. DAILY; LAP TIMER appears as CIRCUIT; DRAG also shows the method), a speed preview, the mount (WRIST / VEHICLE), the current time and a GPS status dot (green = fix / yellow = external device connected but no fix yet / gray = source not ready).

• OK: when the GPS source is ready (dot green or yellow), start recording and enter the Live dashboard; with a gray dot, OK does nothing. With an external device you can also start on a yellow dot, but there is no fix yet — better to wait for green.
• BACK: go back a step to change mode (stays connected).
• RaceBox battery (RaceBox source only, at the left of the speed-unit line): shows the remaining charge as e.g. RB 51%, colored by level (red below 10%, orange below 20%, yellow below 50%, green otherwise). When the RaceBox is plugged in it switches to RB CHG — the moment charging starts the RaceBox’s reported level jumps around (51%→43%→51% in testing), so the watch deliberately shows the charging state rather than that phantom drop.
• Pressed OK and nothing started? Below about 3.5 V the watch shows red LOW BATTERY / CHARGE TO REC — charge it first. With 300 records stored or not enough space it shows STORAGE FULL / DELETE OLD LOGS (delete a few old records, see 9.3); a read/write error shows STORAGE ERROR. Any button clears the message, and that press does not start recording.
• If the standby screen sits for 20 minutes with no recording started and no button pressed, the watch returns to the face (and an external GPS is disconnected); if the GPS source has dropped out (gray dot), it returns after about 5 minutes without a button press.

Go! The Live dashboard shows your performance in real time (next section).

Hold BACK ~2 s; the screen shows Saving... → saved → back to standby, ready to record another session.

The watch can also end and save a session by itself: it shows Saving..., then green SAVED with a yellow reason line, and after about 3 seconds (or any button) returns to standby.

When a session file fills up, the watch splits it automatically (see 6.0): Saving... shows briefly (about 2–6 s) and recording carries on. If 300 records are already stored or space runs out at that point, no new part is started — the part just saved is kept, and the watch returns to standby showing STORAGE FULL.

The real-time screen while recording, showing the most relevant info per mode. Common elements:

• Large speed (center): shows -- without a fix.
• GPS status dot (bottom-left): green/yellow/gray shows fix state.
• Red record dot (bottom-right): recording in progress.
• Live G-force (some modes): the figure at the left of the TOUGE and ROLLING screens is lateral (cornering) G — orange = to the right, cyan = to the left, gray within 0.1 G; it does not indicate acceleration or braking (on the LAP large-speed layout it is white, positive = right). RaceBox is measured; built-in GPS (MAX) is derived; ECO mode shows no value; a Qstarz source supplies no G-force, so the TOUGE screen always reads 0.0 and other screens show none (see 1.2). The RaceBox battery is shown on the standby screen (see 6.4, Step 3).
• If the connection drops, the screen shows Connection lost in red; the RaceBox retries automatically in the background.

Every mode’s Live screen offers three layouts (A/B/C) — the data in the record is the same, only the presentation changes. Set it per mode in SETUP → RACING → page 3, SCREEN LAYOUT (see 10.3); it applies from the next session. Exceptions: in DRAG only QUARTER MILE uses A/B/C (STANDING has its own screen, ROLLING uses the generic screen), and LAP TIMER with GPS AUTO always uses the generic screen.

Pressing OK in the SCREEN LAYOUT list opens a live preview that draws the layout with sample data, so you can confirm before applying.

After choosing DRAG, pick a method (your last choice is remembered):

• LAP TIMER (circuit): with BUTTON, mark each lap on the Live screen with OK/LAP button; the detail page lists best lap, per-lap times and gaps. To count laps automatically, choose GPS AUTO when entering LAP TIMER (see Chapter 7, GPS Auto Lap).
• TOUGE (mountain): free-run recording; detail gives distance, average and top speed, elevation profile and total climb.
• OFF-ROAD: records vehicle attitude. With MOUNT set to VEHICLE, Live first shows the artificial-horizon layout (press UP/DOWN to switch to the layout chosen in SCREEN LAYOUT) — sky/ground fill and a white horizon line follow roll and pitch live, along with R/P readouts, the session’s maximum tilt (MAX), speed and the recording/GPS status dots. The reference (0°) is taken from the attitude at the start of the session and is calibrated automatically, with nothing for you to do: just stay still for a moment while the screen shows LEVELING; STOP TO LEVEL means you are still moving and no reference has been taken yet. On the detail page, P1 shows the session’s maximum tilt as one large total-tilt figure, and P2 is a total-tilt gauge — an outer reference circle with a single needle rotated out from the starting reference; the angle between the two lines is the maximum tilt. The gauge’s left and right do not indicate direction: the left/right and fore/aft split is not implemented yet, so the R-P field reads --. The horizon always uses the watch’s own IMU, so it works with all three sources; tilt on the detail page needs MOUNT=VEHICLE plus a source that records true three-axis acceleration (built-in GPS records the watch’s IMU, a RaceBox its own, and Qstarz none — see 6.0); without both, the detail shows NO TILT / NEEDS VEHICLE MOUNT.
• DAILY DRIVE: lightweight recording throughout; Live shows distance, average speed and total time.

The watch remembers its last fix, so the more recently you used it, the faster next time. Just remember two numbers: 5 minutes and 4 hours:

So you don’t wait repeatedly between sessions, GPS keeps running for 5 minutes after you leave racing mode. Re-enter within that window and the next session starts with almost no wait. After 5 minutes idle, GPS shuts off to save power.

• Back-to-back sessions: leave for under 5 minutes and re-entry needs almost no wait.
• Done for the day: just leave it — GPS turns itself off and won’t quietly drain the battery.

With an external device (RaceBox / Qstarz) you wait for a Bluetooth connection rather than a satellite search: the watch looks for a nearby RaceBox and, once connected, goes to mode selection. If none is found within 5 minutes it reports no device and returns to the face. (No pairing is needed — just switch the RaceBox on nearby.) The GPS source is switched in SETUP → SET GPS, where you can also set built-in GPS precision.

• Before you set off, enter racing mode once outdoors for a first fix — the rest of the day will be fast.
• For back-to-back sessions, try to stay away no more than 5 minutes — with the built-in GPS, the watch keeps the GPS running for 5 minutes after you leave Racing, so re-entering within that window needs almost no wait; after that it shuts down and the next entry needs a new fix.
• Never getting a fix: move to open sky; no fix indoors is normal.

Key events during a session are announced with a tone and vibration, so you don’t have to watch the screen:

Tone and vibration can be switched separately: ALERT TONE / ALERT VIB under SETUP → RACING (both on by default, see 10.3). The two switches govern the events in the table above, including the app connection alerts, except the four STANDING and GPS AUTO rows, which still beep and buzz with the switches off.

In circuit mode (CIRCUIT) the watch can count laps for you. Set the start/finish line once at the start, and every time you cross it the watch logs the lap number and lap time automatically — no more looking down to press a button.

To enter: Menu → CIRCUIT → choose GPS AUTO.

To keep traditional button lapping, choose BUTTON — it works exactly as before.

After recording starts the screen shows SET START LINE. There are two ways to set the line:

Method 1On the move

As you ride/drive across the spot, press the LAP button once. The screen briefly shows SETTING... and it’s done.

Method 2At a standstill

Stop on the start/finish spot and press the LAP button once; the screen shows CALIBRATING. Calibration completes once you set off. Note: lap 1 is timed from the moment you press LAP, so time spent waiting on the line is included in lap 1 — press it when you are ready to go.

• Each time you cross the line from the correct direction, a lap completes automatically: the watch beeps and vibrates and shows the lap number and lap time.
• The line is directional: crossing it the wrong way or passing on a parallel road won’t trigger a false lap.
• Crossings below about 5 km/h (near walking pace) don’t trigger a lap, avoiding false counts from GPS drift while stopped. There is no alert for such a crossing, and the laps either side merge into one long lap — press LAP as you cross if you need it counted.
• For a short time after a lap, it won’t count again — fine even on small karting circuits.

If a lap isn’t detected automatically (e.g. a brief GPS dip), press the LAP button as you cross to mark it manually; the screen shows LAP MARKED.

• If the watch detects that same crossing within about 2 seconds of your press (about 3 seconds with built-in GPS · ECO), it uses the GPS crossing time instead — no double count. After that window, the lap is recorded at the moment you pressed.
• Don’t press LAP after the watch has already counted the lap: about 2 seconds later (about 3 s in ECO) an extra, very short lap is added, and that lap becomes the best lap.

LAP N, ~ LAP N and EST LAP N are notices shown for about 3 seconds after a crossing, at the bottom of the screen (temporarily in place of the total time). CHECK LAP appears at the top while confirming, and also at the bottom when a possible missed pass is flagged. The rest are status words at the top.

GPS signal quality affects crossing-time precision. The watch honestly reports the confidence of each lap:

• Normal lap: good GPS quality, precise lap time.
• ~ Estimated lap: the GPS points either side of the crossing are far apart (about 50–100 m, e.g. crossing fast in ECO), the crossing speed is below about 15 km/h, or speed and distance don’t agree; the time is a small estimate but can still count for best. The best lap is still shown simply as BEST.
• NO BEST high-uncertainty lap: the GPS points either side of the crossing are more than about 100 m apart, so the watch confirms it with the next sample before counting; the lap and time are kept but excluded from the best-lap ranking.
• CHECK LAP: the watch is confirming a crossing with a large GPS gap; if it can’t be confirmed it is treated as a possible missed pass — no lap is added, and the laps either side merge into one long lap.

After holding BACK to stop, the watch returns to standby and briefly shows SAVED and the session’s counted lap total (N LAPS). The record file contains:

In the RECORDS detail summary, LAPS counts official laps only and the best lap is chosen from them; KM and TIME cover the whole session, including warm-up and cool-down.

Each session records at most 200 counted laps (GPS auto lap keeps one warm-up record besides that, so a file holds at most 201). Once you reach the limit:

• The Live screen shows LAP FULL permanently and gives one longer alert (tone/vibration, see 6.8).
• Pressing the LAP button again (OK/LAP button in BUTTON mode) only produces a short error beep and is not recorded as lap 201; GPS auto lap also stops buzzing on later crossings.
• Recording does not stop — distance, time, track and all statistics keep accumulating, and nothing is overwritten, deleted, or split automatically because of the lap count.

• Once synced to the STINT app, the session detail shows the best lap, lap count, average lap time, top speed and lateral G, plus a track map of the whole session (can be expanded to full screen).
• The lap list shows each lap’s time, top speed, max lateral G and gap to the best lap; the warm-up appears as its own row.
• The watch’s ~, EST, NO BEST and CHECK LAP markers currently appear only on the watch, not in the app.

• ✓An open straight section.
• ✓A spot with steady speed and no sharp steering.
• ✕In a tight or hairpin corner.
• ✕Near the pit entrance.
• ✕A section running close and parallel to another road.

Standing-start drag measures the time from a standstill to a target speed. The watch detects your launch automatically to start timing and records the run automatically after the sprint — press OK once before each run to arm, and after that no more button presses are needed, so you can focus on driving. The session itself is saved when you hold BACK to end it.

Each run records three split results, each one the time for that segment alone (not a running total from 0):

0-100 is launch to 100 km/h; 100-200 is 100 to 200; 200-MAX is from passing 200 to the moment the run’s top speed first appears — it climbs as you set new highs and freezes when you lift. 200-MAX is for reference and not used to pick the best run. Splits you don’t reach show --, without affecting the splits you did achieve.

1. Enter RACING and wait for GPS to be ready (external RaceBox, Qstarz or built-in GPS).
2. Choose the DRAG → STANDING method to reach the standby screen.
3. You can only arm (ARM) once the GPS signal is stable; if it’s weak the watch refuses — move to open sky.

• ① Arm (ARM): stop the car and press OK to arm. This tells the watch “the next launch is a timed run.”
• ② Confirm stop (READY): stay fully still for about 1 second; once confirmed it becomes ready. If the car moves before confirmation, it restarts.
• ③ Launch: the instant you hit the throttle and the car moves, timing starts automatically — no accuracy lost to glancing at the watch.
• ④ Sprinting: the screen shows the three splits, the run’s top speed (VMAX) and current speed (CURRENT) live; each split locks in the moment its speed is reached.
• ⑤ Finish: lift off, drop below about 10 km/h and hold for 2 seconds; the run ends and is recorded automatically. The RESULT screen closes after about 3 seconds, or press OK or BACK.

Standing mode supports multiple runs per session: after each run, return to standby and press OK to arm the next. Runs are numbered R1, R2, R3…, up to 200 runs per session; once full the prompt changes to RUN LIMIT and no further run can be armed (everything else in the session still saves normally). On standby the prompt in the middle of the screen reads OK: ARM NEXT RUN (another run can be armed), STOP TO ARM (still moving), GPS NOT READY (no fix yet), GPS SEARCHING... (searching for GPS) or RUN LIMIT (200 runs reached).

Standing mode shows which stage it is in directly on screen:

Accuracy depends entirely on GPS, so the watch has three layers of protection:

If GPS fails after arming but before launch, arming clears automatically — just re-arm from the standby screen.

▲A run aborted by a GPS dropout shows red GPS LOST and INCOMPLETE on the live screen, and GPS LOST on its RECORDS run page. Splits and top speed reached before the dropout are kept; splits not reached show --. The run is excluded from best.

Main menu RECORDS (see Chapter 9) → select the session to view:

• Switch runs: press OK to move between R1/R2/R3… and view each run’s splits.
• BEST marker: the session’s best run (compared by first-split time). Incomplete and GPS LOST runs are excluded.
• Accel curve: the current run’s speed–time curve, drawing only that run, excluding the return trip.
• Meaning of --: on 0-100 / 100-200 it means that speed wasn’t reached (e.g. the venue was too short for 200 km/h) or GPS dropped out before that speed; on 200-MAX it means the run never passed 200, or its top speed came exactly at the moment it passed 200 (lifting just after 200 usually still gives a short time).
• Older records: DRAG records made on earlier firmware now also list 0-100 100-200 200-MAX (segment times) instead of the running totals 0-200 / 0-300.

• The launch threshold is about 3 km/h: after READY, the first GPS sample at or above about 3 km/h is the timing start (driver reaction time is not included, and no rollout is subtracted).
• Splits are computed by interpolating the GPS track, independent of screen refresh rate.
• An external RaceBox (25 Hz) gives higher sample density and finer curves than built-in GPS.
• Speed units (km/h / mph) switch in Settings (Chapter 10); each record remembers the unit used at capture.

There are two places to view records: DOWN at the face (quick overview) and RECORDS in the main menu (per-session detail).

• Display: the first page is an overall summary (sessions, top speed, longest single trip TRIP, max G); then one stats page per mode that has records.
• Scope: the last 10 records — this page always summarizes only the newest 10 records, regardless of how many records RECORDS actually holds (see 9.3). Tilt records also take up places among these 10, but they are not counted as sessions or in any of the stats. With none it shows NO RACE YET.
• Buttons: UP/DOWN page; pressing UP on the first page or DOWN on the last slides back to the face; BACK returns to the face.

On entry it loads that session (large files show READING LOG briefly). Use DOWN next/UP previous to page, BACK to the list. Page count and content vary by mode; in every mode (tilt records included) the second-to-last page is INFO (session info, see below) and the last page is Delete (see 9.3):

More page examples per mode

The INFO page gathers the recording conditions of the session, so you can check afterwards which GPS was used, at what rate, and how it ended. Rows that don’t apply are hidden; OK does nothing on this page.

• Delete one: in a session’s detail, page to the last page DELETE LOG? → OK → confirm again → deleted and back to the list.
• Delete all: the last row of the record list DELETE ALL → OK → confirm.
• SETUP → Delete does not delete Racing records: it resets the achievement data (lifetime distance / drives / today’s top speed) to zero and keeps your watch face choice. To delete Racing records, use DELETE ALL above (see 10.6).

Main menu → SETUP, containing:

Three screens: status page → settings page → selection list.

• Status page: shows current source and precision; press OK for settings.
• Settings page: SOURCE (RACEBOX / INTERNAL GPS / QSTARZ); PRECISION (MAX highest update rate / ECO power-saving lower rate). PRECISION only applies to the built-in GPS; with RaceBox or Qstarz it is fixed at DEFAULT.
• Selection list: the current value has a filled dot and the focused row is yellow; OK saves.
• When it applies: settings save immediately, but the actual source/rate takes effect only the next time you enter Racing.

One item per page, set in turn:

Time → Set Time opens a text submenu with three items:

• GPS SYNC: sync the time from GPS right away (go to an open outdoor area and wait for a fix). It is unaffected by the auto-sync switch and always available. If there is still no fix after 10 minutes it shows TIME OUT and returns to the face after about 2 seconds.
• MANUAL SET: set date and time by hand — edit year → month → day → hour → minute field by field (the field being edited has a flashing underline), UP/DOWN change the value (hold for fast change), OK moves to the next field, and OK on the last field writes it (seconds reset to zero); BACK cancels. The year range is 2025–2037; your input is treated as local time in the current time zone, so check the time zone first.
• AUTO SYNC: the auto-sync switch (ON by default). When off, the watch will not overwrite your manually set time from GPS; running GPS SYNC yourself still syncs it.

RACING settings span 3 pages. UP/DOWN move within a page and turn to the next page at either end (the dots along the right edge show the current page).

• How to enter: System Settings → Alarm. There are 5, each independent.
• Set each one: type (Off / Daily / Once / Weekdays) → hour → minute, advancing with OK; the editing field blinks, adjust with UP/DOWN (hold to change fast).
• Ringing: at the set time an alarm icon shows, beeping and vibrating every 3 s, stopping automatically after up to 60 s; any key dismisses it.

• Where to set: System Settings → Heart Rate. You can set: HR source (wrist optical toggle / external strap Bluetooth pairing), resting HR (scheduled resting-rate measurement with history), max HR (auto 220 − age, or custom) and the HR monitoring switch.
• See live HR: first turn on the HR monitoring switch above (off by default), then from the face UP → TILT (FreeTilt) → UP → Compass → UP to the HR monitor page (4-hour bar chart + live HR, returning to the face after ~60 s idle). With HR monitoring off, UP on the Compass goes straight to the Barometer (see 4.3).

• Reset: system reset — every setting goes back to default (language English, time zone UTC+8, GPS source RACEBOX with the RaceBox pairing cleared, Set Time AUTO SYNC ON), achievement data is reset to zero and the watch face returns to the default Triple Stack (preview name OVERVIEW); the clock itself is not reset, but the displayed time may change once the time zone is back at UTC+8. all reset — same as system reset, then an automatic reboot. Both prompt for confirmation first, and neither deletes Racing records; to delete records, use DELETE ALL in RECORDS (see 9.3).
• About: shows the product logo, serial number (SN), firmware version (VER), Bluetooth address and the last almanac update time.

Achievement data (lifetime distance / drives / today’s top speed, see 4.6) is stored separately from the record files: deleting records in RECORDS does not affect your totals, while SETUP → Delete and both resets zero the achievements but do not delete session records:

The [Companion App] is the STINT watch’s track companion app. Use it to connect to the watch, sync track logs, review post-session data and manage device status. All screens in this chapter are actual app screens.

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Before you start, check these:

• Phone Bluetooth is on.
• The STINT watch is powered on and near the phone.
• The [Companion App] is open. On first launch a welcome screen (cloud backup sign-in) appears first; tap Browse first to skip it — you can sign in later under Settings → STINT ID. Then start from “Search for watch” on the home screen.

1. The status row at the top of the home screen reads Watch · not connected, and the “Next step” card below it says Connect your watch.
2. Tap Search for watch to begin pairing.
3. While disconnected you can still browse synced sessions and use speed alerts (the home screen notes that neither needs a connection).

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1. Tap Search for watch on the home screen.
2. The app begins searching for nearby watches (about 8 seconds); keep the watch on and near the phone.
3. When the search ends, a Select your watch list appears (names are STINT GTM plus four characters; see 11.3). Even if only one watch is found, tap your watch.
4. The app establishes a link with the watch — just a moment.
5. Once linked, the app briefly shows Connected and returns to the previous screen by itself; the home status row then shows a green dot and the watch name.

Don’t worry when you see Watch not found — it usually doesn’t mean a fault. Check in order:

1. Is the watch powered on.
2. Is the watch near the phone.
3. Is the phone’s Bluetooth on.
4. Is the watch connected to another device (one phone at a time).
5. Tap Search again.

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Once connected, the status row at the top of the home screen changes:

1. The connected watch name, in the form STINT GTM plus four characters (e.g. STINT GTM CA01; see 11.3).
2. A green dot before the name means connected; after you have synced, the last sync time follows the name (e.g. “synced 5 min ago”).
3. Tap the status row (Device › on the right) to open the “My Devices” page with the firmware version and RaceBox (see 11.5).
4. The “Next step” card below becomes Sync to phone; tap Sync sessions to read the watch’s records.

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The My Devices page (the Device tab at the bottom) shows the watch’s firmware version, connection state and last sync time, plus the RaceBox currently assigned to the watch.

1. Watch info: firmware, connection state, last sync. Battery currently shows “—” (the app cannot read the watch battery yet).
2. RaceBox card: shows “Not paired” or “Paired · address”, with a note that the app reads RaceBox status through the watch.
3. Pair RaceBox / Change RaceBox button: assigns a RaceBox in the app (currently this does not affect which unit the watch actually connects to — see the note below).

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1. Make sure the watch is connected.
2. Tap Sync sessions on the home screen.
3. The app reads the session list from the watch (no re-search or reconnect).
4. Choose the Race Log to sync.
5. The app downloads the track log, showing a progress percentage.
6. When done, view the post-session data in the app.

Labels in the session list mean:

If the signal is only briefly unstable during a download, the app retries a few times by itself. If the connection really drops, the session’s row shows a red error (e.g. “Download failed: …”) and the app also says “Watch disconnected, please reconnect”. Then:

• Bring the phone near the watch.
• In the Device tab tap Reconnect (or tap Search for watch on the home screen) to connect again.
• Tap Sync sessions on the home screen, then tap that session again to download it again.

No new sessions (“no new sessions on the watch”) isn’t an error — it means the watch currently holds no records at all to download.

The watch doesn’t delete records by itself, so as long as old sessions remain on it, the app lists them as usual and marks the imported ones “Synced” (see 11.6) instead of showing this screen. After recording a new session (see Chapter 6), come back and tap Sync sessions.

Besides the app, you can connect the watch to a computer: it appears as a flash drive, with sessions stored in the RACELOG folder (each filename is the recording start time encoded as an 8-digit hexadecimal number, e.g. 6AB4C368.BIN). The desktop parser (double-click parse.bat) produces track maps, spreadsheets and speed charts (see the Chapter 9 walkthrough).

The watch’s GPS source and built-in precision can be changed from the app as well as on the watch (see 10.1), in the Watch section of the Settings tab at the bottom (the watch must be connected; when it isn’t, the options are greyed out with the hint that they can be set after connecting the watch):

• GPS source: Built-in or RaceBox.
• Built-in output rate: appears only when “Built-in” is selected; choose Highest or Power saving — these correspond to MAX / ECO on the watch (see 10.1).
• After changing it the app notes that “the change applies the next time you enter Race” — the same rule as on the watch; the session in progress is unaffected.

Every session can be exported as a KML track file (openable in Google Earth and similar map software), or turned into an achievement image to share. All five modes are supported. The session page also has Export CSV / GPX: CSV has one sample per row and opens in Excel or any spreadsheet; GPX is the standard GPS track format for map and analysis software. Both contain coordinates, and the start/end handling follows the same per-mode defaults as KML (see below).

• Choose Export KML on the session page and pick how much of the route to include:
  • Full track — includes the exact start and end points.
  • Protect start/end — automatically removes the track within a 300 m radius of the start and end points (any part of the route that passes near those points mid-way is removed too).
• The default depends on the mode: circuit and DRAG default to the full track (there is no privacy concern on a circuit); daily, touge and off-road default to protecting the start and end. You can switch at any time.

• Share achievement produces a result card (1080×1080) that you can post to social media or send to friends with the system share sheet.
• The card itself is safe: the route keeps only an anonymized shape and contains no place names, coordinates, start/end points or any GPS positioning data.

Tilt recordings made with FreeTilt (see 4.5) can be synced to the app, which can overlay the attitude onto your driving video and export a new file. Race sessions can be overlaid too: tap Overlay video on the session summary, or start from the home-screen tool Video OSD (pick the videos first, then the record), to burn speed, distance, G-force and similar data into the video; alignment and export work as described below.

1. Sync: pick a tilt recording in the watch record browser and download it over Bluetooth. Once downloaded it appears in the session list alongside your sessions, marked as a tilt recording.
2. Pick a video: choose driving footage from the same period. The app aligns them automatically using the watch recording’s timestamps and the video’s capture time; you can fine-tune by hand if they drift.
3. Export: the artificial horizon and R/P values are overlaid onto the video and exported as a new file. One tilt recording can be applied to several videos at once for batch export.

• The watch never deletes old records automatically; RECORDS browses up to 300 records, and you must clear space yourself when it fills. Back up important records early.
• With 300 records stored in total, or not enough space, neither sessions nor FreeTilt can start a new recording (it shows STORAGE FULL / DELETE OLD LOGS) — the watch never deletes old records to make room. Delete a few old records to continue.
• G-force from the built-in GPS (MAX) is derived, has no vertical component, and is skipped at low speed (below 2 km/h neither axis, 2–10 km/h longitudinal only); it is less accurate than a RaceBox measurement. ECO mode samples too sparsely to provide G-force at all.
• Qstarz sessions show no G-force on the watch (the device’s mounting orientation is unverified); once synced, the mobile app derives it itself.
• Off-road attitude / tilt requires MOUNT=VEHICLE and a brief stationary moment during the session for the watch to take its reference (on the pre-start confirmation screen, or by stopping for a few seconds after starting); otherwise it shows NO TILT / NEEDS VEHICLE MOUNT. Wrist-worn (WRIST) sessions provide no attitude data, and Qstarz sessions carry no tilt data at all (see 6.3).
• Qstarz’s real update rate is limited by the Bluetooth connection interval to about 5.6 Hz — lower than a RaceBox (25 Hz) and close to built-in GPS at MAX (5 Hz).
• Normal screens return to the face after about 11 minutes idle; a session in progress (Live) does not return to the face for inactivity, but it ends automatically when MAX REC is reached, after a long stop, or on low battery (see 6.4).
• Overly long sessions split into multiple sessions automatically (see 6.0), resetting timer and distance.
• The LAP TIMER detail page shows speed fixed in km/h, not converted by the speed-unit setting.

Taiwan NCC statement (certification no.: [TBD]) — reproduced in the original Chinese as required by law

取得審驗證明之低功率射頻器材，非經核准，公司、商號或使用者均不得擅自變更頻率、加大功率或變更原設計之特性及功能。低功率射頻器材之使用不得影響飛航安全及干擾合法通信；經發現有干擾現象時，應立即停用，並改善至無干擾時方得繼續使用。前述合法通信，指依電信管理法規定作業之無線電通信。低功率射頻器材須忍受合法通信或工業、科學及醫療用電波輻射性電機設備之干擾。

United States FCC statement (FCC ID: [TBD])

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

EU CE / RED: This product complies with the essential requirements of the EU Radio Equipment Directive (RED 2014/53/EU). For the full Declaration of Conformity (DoC), contact the manufacturer. (CE marking and EU representative details: [TBD])

Warranty: one-year limited warranty — 12 months from the date of purchase; where no proof of purchase can be provided, 15 months from the date of manufacture. Service is provided within Taiwan (R.O.C.) only; customers outside Taiwan bear the round-trip shipping, duties and customs charges. To request service, provide the product serial number and proof of purchase; we also recommend including the diagnostic code produced by the app’s “Device Check”, which resolves most cases without shipping the unit. The battery is an exception: if its capacity falls below 80% within 300 charge cycles and this is confirmed by inspection, it is treated as a defect and remains covered. The warranty card supplied with the product governs in full. (Support contact: [TBD]). Damage caused by improper use, use contrary to this manual, unauthorized disassembly or the use of non-original accessories is not covered (see “Safety and Disclaimer”, item 7).