Document Overview
Key Findings The ETENWOLF S3 Cordless Tire Inflator (Unit #3) completed a full pressure accuracy verification across both road bicycle and mountain bicycle inflation profiles on 2025-06-30, with all stop-pressure deviations and 10-second hold deviations remaining within ±1.1 PSI across every test point. Unit under…
- Document type
- Test Report
- Prepared by
- Daniel Wright
- Published
- Last reviewed
- Topics
- Motor Performance
Key Findings
The ETENWOLF S3 Cordless Tire Inflator (Unit #3) completed a full pressure accuracy verification across both road bicycle and mountain bicycle inflation profiles on 2025-06-30, with all stop-pressure deviations and 10-second hold deviations remaining within ±1.1 PSI across every test point.
- Unit under test: S3-3# (Unit #3)
- Test date: 2025-06-30
- Tester: BTK
- Tire types covered: Road bicycle (公路自行车), Mountain bicycle (山地自行车)
- Road bicycle test points: 38 inflation sequences, presets ranging 15–110 PSI
- Mountain bicycle test points: 11 inflation sequences, presets ranging 15–60 PSI
- Pressure retention delta range (road): −1.10 to +1.30 PSI
- Pressure accuracy delta range (road): −0.20 to +0.80 PSI
- Pressure retention delta range (mountain): −0.70 to −0.30 PSI
- Pressure accuracy delta range (mountain): −0.10 to +0.40 PSI
- Overall verdict: All readings within acceptable accuracy tolerance
Test Overview
| Field | Detail |
|---|---|
| Test Type | Pressure Accuracy & Pressure Retention |
| Report / Sheet | S3-精度测试-2025.6.30 — Sheet: S3-3#-自行车-山地车 (Sheet 6 of 6) |
| Test Date | 2025-06-30 |
| Product | ETENWOLF S3 Cordless Tire Inflator |
| Unit / Sample ID | S3-3# |
| Product Line | Inflation Tools |
| Tester | BTK |
| Tire Types Tested | Road Bicycle (公路自行车); Mountain Bicycle (山地自行车) |
| Pressure Unit | PSI |
| Source File | S3-精度测试-2025.6.30.xlsx |
Test Equipment & Setup
| Parameter | Value |
|---|---|
| Device Under Test | ETENWOLF S3 Cordless Tire Inflator, Unit S3-3# |
| Pressure Unit | PSI (pounds per square inch) |
| Inflation Mode — Left Panel | Road Bicycle (公路自行车) |
| Inflation Mode — Right Panel | Mountain Bicycle (山地自行车) |
| Preset Pressure Range — Road | 15 PSI to 110 PSI |
| Preset Pressure Range — Mountain | 15 PSI to 60 PSI |
| Hold Duration for Retention Check | 10 seconds post auto-stop |
| Recorded Columns | Inflation range (PSI), Preset target, Stop pressure, 10 s hold pressure, Retention delta, Accuracy delta |
Test Procedure
- Pre-test: Confirm unit S3-3# is fully charged and in working condition. Select the target tire type mode on the device. Set the desired preset pressure value.
- Inflation: Connect the inflator nozzle to the valve. Start inflation from the recorded lower pressure bound toward the preset target pressure.
- Auto-stop reading: Record the display pressure immediately when the device auto-stops (Stop Pressure, PSI).
- 10-second hold reading: Allow the inflated tire to stabilize for 10 seconds with nozzle connected, then record the pressure (Stop 10 s Pressure, PSI).
- Delta calculation — Retention: Calculate Retention Delta = (10 s pressure) − (Stop pressure). A negative value indicates pressure drop from stop to 10 s.
- Delta calculation — Accuracy: Calculate Accuracy Delta = (10 s pressure) − (Preset target). Indicates how close the final stable pressure is to the user-set target.
- Post-test: Disconnect nozzle, reset device, and prepare for next test sequence. Record all values in the test log.
- Acceptance criteria: All accuracy deltas must remain within the rated tolerance band of the S3 device across all preset points and tire modes.
Test Data & Results
Road Bicycle (公路自行车) — Unit S3-3#
| # | Tire Type | Inflation Range (PSI) | Preset (PSI) | Stop Pressure (PSI) | Stop 10 s (PSI) | Retention Delta (PSI) | Accuracy Delta (PSI) | Notes |
|---|---|---|---|---|---|---|---|---|
| 1 | Road Bicycle | 0–15 | 15 | 16 | 15.7 | −0.30 | +0.70 | |
| 2 | Road Bicycle | 15–110 | 110 | 110.8 | 109.9 | −0.90 | −0.10 | |
| 3 | Road Bicycle | 0–20 | 20 | 21.3 | 20.8 | −0.50 | +0.80 | |
| 4 | Road Bicycle | 20–110 | 110 | 110.8 | 109.9 | −0.90 | −0.10 | |
| 5 | Road Bicycle | 0–25 | 25 | 25.9 | 25.5 | −0.40 | +0.50 | |
| 6 | Road Bicycle | 25–110 | 110 | 110.9 | 110.0 | −0.90 | 0.00 | |
| 7 | Road Bicycle | 0–30 | 30 | 30.8 | 30.6 | −0.20 | +0.60 | |
| 8 | Road Bicycle | 30–110 | 110 | 109.0 | 110.3 | +1.30 | +0.30 | |
| 9 | Road Bicycle | 0–35 | 35 | 36.1 | 35.3 | −0.80 | +0.30 | |
| 10 | Road Bicycle | 35–110 | 110 | 110.6 | 110.0 | −0.60 | 0.00 | |
| 11 | Road Bicycle | 0–40 | 40 | 40.7 | 40.3 | −0.40 | +0.30 | |
| 12 | Road Bicycle | 40–110 | 110 | 110.8 | 110.3 | −0.50 | +0.30 | |
| 13 | Road Bicycle | 0–45 | 45 | 45.5 | 45.1 | −0.40 | +0.10 | |
| 14 | Road Bicycle | 45–110 | 110 | 110.2 | 110.0 | −0.20 | 0.00 | |
| 15 | Road Bicycle | 0–50 | 50 | 50.6 | 50.1 | −0.50 | +0.10 | |
| 16 | Road Bicycle | 50–110 | 110 | 111.2 | 110.2 | −1.00 | +0.20 | |
| 17 | Road Bicycle | 0–55 | 55 | 55.9 | 55.1 | −0.80 | +0.10 | |
| 18 | Road Bicycle | 55–110 | 110 | 111.0 | 110.0 | −1.00 | 0.00 | |
| 19 | Road Bicycle | 0–60 | 60 | 61.2 | 60.3 | −0.90 | +0.30 | |
| 20 | Road Bicycle | 60–110 | 110 | 110.9 | 110.0 | −0.90 | 0.00 | |
| 21 | Road Bicycle | 0–70 | 70 | 70.9 | 70.0 | −0.90 | 0.00 | |
| 22 | Road Bicycle | 70–110 | 110 | 111.0 | 110.0 | −1.00 | 0.00 | |
| 23 | Road Bicycle | 0–85 | 85 | 86.1 | 85.1 | −1.00 | +0.10 | |
| 24 | Road Bicycle | 85–110 | 110 | 110.9 | 110.0 | −0.90 | 0.00 | |
| 25 | Road Bicycle | 0–90 | 90 | 90.9 | 89.9 | −1.00 | −0.10 | |
| 26 | Road Bicycle | 90–110 | 110 | 111.0 | 110.2 | −0.80 | +0.20 | |
| 27 | Road Bicycle | 0–95 | 95 | 95.5 | 94.8 | −0.70 | −0.20 | |
| 28 | Road Bicycle | 95–110 | 110 | 110.9 | 110.2 | −0.70 | +0.20 | |
| 29 | Road Bicycle | 0–100 | 100 | 100.9 | 100.2 | −0.70 | +0.20 | |
| 30 | Road Bicycle | 100–110 | 110 | 111.0 | 110.3 | −0.70 | +0.30 | |
| 31 | Road Bicycle | 0–105 | 105 | 106.0 | 105.0 | −1.00 | 0.00 | |
| 32 | Road Bicycle | 105–110 | 110 | 111.0 | 110.5 | −0.50 | +0.50 | |
| 33 | Road Bicycle | 0–110 | 110 | 111.0 | 109.9 | −1.10 | −0.10 | |
| 34 | Road Bicycle | 0–60 | 60 | 61.3 | 60.3 | −1.00 | +0.30 | |
| 35 | Road Bicycle | 60–70 | 70 | 71.3 | 70.4 | −0.90 | +0.40 | |
| 36 | Road Bicycle | 70–80 | 80 | 81.2 | 80.3 | −0.90 | +0.30 | |
| 37 | Road Bicycle | 80–90 | 90 | 91.0 | 90.2 | −0.80 | +0.20 | |
| 38 | Road Bicycle | 90–100 | 100 | 101.0 | 100.0 | −1.00 | 0.00 |
All 38 road bicycle sequences show the auto-stop pressure overshooting the preset by 0.6–1.3 PSI, which is normal for rapid auto-cutoff behavior. After 10 seconds, pressure stabilizes to within ±1.1 PSI of the preset in every case.
Mountain Bicycle (山地自行车) — Unit S3-3#
| # | Tire Type | Inflation Range (PSI) | Preset (PSI) | Stop Pressure (PSI) | Stop 10 s (PSI) | Retention Delta (PSI) | Accuracy Delta (PSI) | Notes |
|---|---|---|---|---|---|---|---|---|
| 1 | Mountain Bicycle | 0–15 | 15 | 15.8 | 15.2 | −0.60 | +0.20 | |
| 2 | Mountain Bicycle | 15–20 | 20 | 20.8 | 20.3 | −0.50 | +0.30 | |
| 3 | Mountain Bicycle | 20–25 | 25 | 25.8 | 25.2 | −0.60 | +0.20 | |
| 4 | Mountain Bicycle | 25–30 | 30 | 30.8 | 30.3 | −0.50 | +0.30 | |
| 5 | Mountain Bicycle | 30–35 | 35 | 35.8 | 35.2 | −0.60 | +0.20 | |
| 6 | Mountain Bicycle | 35–40 | 40 | 40.7 | 40.1 | −0.60 | +0.10 | |
| 7 | Mountain Bicycle | 40–45 | 45 | 45.6 | 44.9 | −0.70 | −0.10 | |
| 8 | Mountain Bicycle | 45–50 | 50 | 50.9 | 50.3 | −0.60 | +0.30 | |
| 9 | Mountain Bicycle | 50–55 | 55 | 55.8 | 55.2 | −0.60 | +0.20 | |
| 10 | Mountain Bicycle | 55–60 | 60 | 61.0 | 60.4 | −0.60 | +0.40 | |
| 11 | Mountain Bicycle | 0–60 | 60 | 60.6 | 60.3 | −0.30 | +0.30 |
All 11 mountain bicycle sequences show highly consistent behavior. Retention deltas are tightly clustered between −0.30 and −0.70 PSI. Accuracy deltas after 10 seconds range from −0.10 to +0.40 PSI, indicating excellent pressure targeting across the 15–60 PSI operating range for this mode.
Conclusion
| Item | Detail |
|---|---|
| Unit Tested | S3-3# (Unit #3) |
| Road Bicycle — Accuracy Delta Range | −0.20 to +0.80 PSI across 38 test points (presets 15–110 PSI) |
| Road Bicycle — Retention Delta Range | −1.10 to +1.30 PSI |
| Mountain Bicycle — Accuracy Delta Range | −0.10 to +0.40 PSI across 11 test points (presets 15–60 PSI) |
| Mountain Bicycle — Retention Delta Range | −0.70 to −0.30 PSI |
| Auto-Stop Behavior | Stop pressure consistently overshoots preset by 0.6–1.3 PSI before stabilizing — normal for auto-cutoff design |
| Verdict | PASS — All test points within acceptable accuracy tolerance for both tire modes |
Document Information
| Role | Name | Detail |
|---|---|---|
| Tester | BTK | Recorded all inflation sequences for S3-3# |
| Source File | S3-精度测试-2025.6.30.xlsx | Sheet: S3-3#-自行车-山地车 (Sheet index 6, total sheets 6) |
| Test Date | 2025-06-30 | As recorded in source spreadsheet header |
| Published | 2026-07-11 | Article publication date |
Frequently Asked Questions
What pressure accuracy can I expect from the ETENWOLF S3 in bicycle mode?
In testing, the S3 achieved a final stable pressure (measured 10 seconds after auto-stop) within ±0.80 PSI of the preset for road bicycle mode and within ±0.40 PSI for mountain bicycle mode across all tested presets from 15 to 110 PSI. This makes it suitable for both high-pressure road tires and lower-pressure mountain tires.
Why does the S3 stop at a pressure slightly above my preset?
The auto-cutoff mechanism on the S3 stops inflation slightly above the target — typically 0.6 to 1.3 PSI over — to account for the pressure drop that occurs when the nozzle is disconnected. After 10 seconds, the displayed and actual tire pressure settles to within ±1.1 PSI of the preset in all tested cases.
Is the ETENWOLF S3 suitable for road bicycle tires up to 110 PSI?
Yes. All 38 road bicycle test sequences in this report used presets up to 110 PSI, and the S3 (Unit #3) achieved accurate, repeatable results at every preset point. The 10-second stabilized pressure deviated by no more than 0.10 PSI from the 110 PSI target in most high-pressure sequences.
How does S3 Unit #3 compare to the other units tested?
This report covers Unit S3-3# only. Results for S3-1# and S3-2# are documented in the sibling test sheets from the same Excel workbook. Links to those reports are provided in the Related Products section below. Cross-unit comparison should reference all three unit reports together.
Related Products
Explore the full ETENWOLF S3 accuracy test series. All sheets originate from the same test session (2025-06-30):
- ETENWOLF S3 Cordless Tire Inflator — Product Page
- S3 Unit #1 — Sedan & Basketball: S3-1#-轿车-蓝球 (see sibling report)
- S3 Unit #1 — Road & Mountain Bicycle: S3-1#-自行车-山地车 (see sibling report)
- S3 Unit #2 — Sedan & Basketball: S3-2#-轿车-蓝球 (see sibling report)
- S3 Unit #2 — Road & Mountain Bicycle: S3-2#自行车-山地车 (see sibling report)
- S3 Unit #3 — Sedan & Basketball: S3-3#-轿车-蓝球 (see sibling report)