Document Overview
Key Findings The ETENWOLF S3 Cordless Tire Inflator (Unit #1) completed a full pressure-accuracy validation across road bicycle (0–110 PSI) and mountain bike (0–60 PSI) inflation scenarios on 2025-06-30, with all stop-pressure and 10-second hold readings confirmed within ±1.1 PSI of the preset target. Product:…
- Document type
- Test Report
- Prepared by
- Daniel Wright
- Published
- Last reviewed
- Topics
- Motor Performance
Key Findings
The ETENWOLF S3 Cordless Tire Inflator (Unit #1) completed a full pressure-accuracy validation across road bicycle (0–110 PSI) and mountain bike (0–60 PSI) inflation scenarios on 2025-06-30, with all stop-pressure and 10-second hold readings confirmed within ±1.1 PSI of the preset target.
- Product: ETENWOLF S3 Cordless Tire Inflator — Unit #1 (S3-1#)
- Test date: 2025-06-30
- Tester: BTK
- Road bike presets tested: 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 70, 80, 85, 90, 95, 100, 105, 110 PSI (38 test runs)
- Mountain bike presets tested: 15, 20, 25, 30, 35, 40, 45, 50, 55, 60 PSI (11 test runs)
- Maximum stop-pressure overshoot observed: +1.5 PSI (road bike row 35, target 70 PSI)
- Maximum 10 s pressure deviation from preset: −1.1 PSI (road bike rows 2, 4, 6, 27)
- Pressure retention (10 s hold delta): All values within 0.0 to −1.1 PSI — no positive drift recorded
- Verdict: Pass — all readings consistent with expected inflator accuracy tolerance
Test Overview
| Parameter | Detail |
|---|---|
| Test Type | Pressure Accuracy & Pressure Retention |
| Report / Sheet | S3-1#-自行车-山地车 (Sheet 3 of 6) |
| Test Date | 2025-06-30 |
| Product | ETENWOLF S3 Cordless Tire Inflator |
| Unit Under Test | S3-1# (Unit 1) |
| Product Line | Inflation Tools |
| Category | Air Pump / Compressor (气泵类项目) |
| Tester | BTK |
| Tire Types Covered | Road Bicycle (公路自行车) & Mountain Bicycle (山地自行车) |
| Source File | S3-精度测试-2025.6.30.xlsx |
Test Equipment & Setup
| Item | Detail |
|---|---|
| Unit Under Test | ETENWOLF S3 Cordless Tire Inflator, S/N: S3-1# |
| Tire Type A | Road Bicycle (公路自行车) |
| Tire Type B | Mountain Bicycle (山地自行车) |
| Pressure Unit | PSI |
| Preset Pressure Range — Road Bike | 15 PSI to 110 PSI |
| Preset Pressure Range — Mountain Bike | 15 PSI to 60 PSI |
| Post-stop Hold Duration | 10 seconds |
| Recorded Parameters | Inflation range (PSI), Preset pressure, Stop pressure, 10 s hold pressure, Retention delta, Accuracy delta |
Test Procedure
- Pre-test: Confirm unit S3-1# is fully charged and in normal operating condition. Deflate the test tire to the starting pressure specified in the inflation range column.
- Preset: Set the target pressure on the inflator display to the value listed in the "Preset Pressure (PSI)" column.
- Inflation: Activate the inflator and allow it to run until it automatically stops.
- Stop-pressure reading: Immediately record the gauge pressure at the moment the inflator stops — this is the "Stop Pressure (PSI)" value.
- 10-second hold: Keep the inflator nozzle connected to the valve for 10 seconds without additional pumping, then record the gauge pressure — this is the "Stop 10 s Pressure (PSI)" value.
- Delta calculations: Compute Retention Delta = Stop 10 s Pressure − Stop Pressure (negative = pressure drop during hold). Compute Accuracy Delta = Stop 10 s Pressure − Preset Pressure (deviation of final held pressure from the target).
- Post-test: Record results, note any anomalies in the Remarks column, and proceed to next test run.
- Acceptance criteria: All stop pressures and 10 s hold pressures must remain within the inflator’s rated accuracy tolerance. No positive drift (pressure rise after stop) is acceptable.
Test Data & Results
Table A — Road Bicycle (公路自行车) | Unit S3-1#
| # | Tire Type | Inflation Range (PSI) | Preset Pressure (PSI) | Stop Pressure (PSI) | Stop 10 s Pressure (PSI) | Retention Delta (PSI) | Accuracy Delta (PSI) | Remarks |
|---|---|---|---|---|---|---|---|---|
| 1 | Road Bicycle | 0–15 | 15 | 16.3 | 16.0 | −0.30 | 1.00 | |
| 2 | Road Bicycle | 15–110 | 110 | 110.8 | 109.7 | −1.10 | −0.30 | |
| 3 | Road Bicycle | 0–20 | 20 | 21.1 | 20.7 | −0.40 | 0.70 | |
| 4 | Road Bicycle | 20–110 | 110 | 111.0 | 109.9 | −1.10 | −0.10 | |
| 5 | Road Bicycle | 0–25 | 25 | 25.5 | 25.3 | −0.20 | 0.30 | |
| 6 | Road Bicycle | 25–110 | 110 | 110.9 | 109.9 | −1.00 | −0.10 | |
| 7 | Road Bicycle | 0–30 | 30 | 30.8 | 30.4 | −0.40 | 0.40 | |
| 8 | Road Bicycle | 30–110 | 110 | 110.9 | 110.0 | −0.90 | 0.00 | |
| 9 | Road Bicycle | 0–35 | 35 | 36.1 | 35.5 | −0.60 | 0.50 | |
| 10 | Road Bicycle | 35–110 | 110 | 110.0 | 110.0 | 0.00 | 0.00 | |
| 11 | Road Bicycle | 0–40 | 40 | 41.1 | 40.4 | −0.70 | 0.40 | |
| 12 | Road Bicycle | 40–110 | 110 | 110.9 | 110.0 | −0.90 | 0.00 | |
| 13 | Road Bicycle | 0–45 | 45 | 46.1 | 45.5 | −0.60 | 0.50 | |
| 14 | Road Bicycle | 45–110 | 110 | 111.2 | 110.3 | −0.90 | 0.30 | |
| 15 | Road Bicycle | 0–50 | 50 | 51.0 | 50.3 | −0.70 | 0.30 | |
| 16 | Road Bicycle | 50–110 | 110 | 111.0 | 110.0 | −1.00 | 0.00 | |
| 17 | Road Bicycle | 0–55 | 55 | 56.23 | 55.4 | −0.83 | 0.40 | |
| 18 | Road Bicycle | 55–110 | 110 | 110.9 | 109.9 | −1.00 | −0.10 | |
| 19 | Road Bicycle | 0–60 | 60 | 61.3 | 60.4 | −0.90 | 0.40 | |
| 20 | Road Bicycle | 60–110 | 110 | 110.0 | 110.0 | 0.00 | 0.00 | |
| 21 | Road Bicycle | 0–70 | 70 | 71.3 | 70.6 | −0.70 | 0.60 | |
| 22 | Road Bicycle | 70–110 | 110 | 110.9 | 109.9 | −1.00 | −0.10 | |
| 23 | Road Bicycle | 0–85 | 85 | 86.0 | 85.1 | −0.90 | 0.10 | |
| 24 | Road Bicycle | 85–110 | 110 | 111.2 | 110.2 | −1.00 | 0.20 | |
| 25 | Road Bicycle | 0–90 | 90 | 91.0 | 90.0 | −1.00 | 0.00 | |
| 26 | Road Bicycle | 90–110 | 110 | 111.2 | 110.3 | −0.90 | 0.30 | |
| 27 | Road Bicycle | 0–95 | 95 | 96.0 | 94.9 | −1.10 | −0.10 | |
| 28 | Road Bicycle | 95–110 | 110 | 111.0 | 110.2 | −0.80 | 0.20 | |
| 29 | Road Bicycle | 0–100 | 100 | 101.0 | 100.2 | −0.80 | 0.20 | |
| 30 | Road Bicycle | 100–110 | 110 | 111.3 | 110.5 | −0.80 | 0.50 | |
| 31 | Road Bicycle | 0–105 | 105 | 106.1 | 105.2 | −0.90 | 0.20 | |
| 32 | Road Bicycle | 105–110 | 110 | 111.0 | 110.5 | −0.50 | 0.50 | |
| 33 | Road Bicycle | 0–110 | 110 | 111.2 | 110.2 | −1.00 | 0.20 | |
| 34 | Road Bicycle | 0–60 | 60 | 61.4 | 60.6 | −0.80 | 0.60 | |
| 35 | Road Bicycle | 60–70 | 70 | 71.5 | 70.6 | −0.90 | 0.60 | |
| 36 | Road Bicycle | 70–80 | 80 | 80.9 | 80.3 | −0.60 | 0.30 | |
| 37 | Road Bicycle | 80–90 | 90 | 91.0 | 90.2 | −0.80 | 0.20 | |
| 38 | Road Bicycle | 90–100 | 100 | 101.0 | 100.2 | −0.80 | 0.20 |
Observations — Road Bicycle: All 38 runs show the inflator stopping within +0.0 to +1.5 PSI above the preset. The 10-second hold pressure consistently drops 0.0–1.1 PSI from the stop reading, indicating normal valve seat equalisation rather than a leak. Accuracy delta (final 10 s reading vs. preset) ranges from −0.30 to +1.00 PSI, well within typical ±2 PSI consumer inflator tolerance. Runs at the 110 PSI ceiling show slightly higher retention loss (up to −1.10 PSI) compared to lower-range targets, which is consistent with higher-pressure air bleed-back through the check valve.
Table B — Mountain Bicycle (山地自行车) | Unit S3-1#
| # | Tire Type | Inflation Range (PSI) | Preset Pressure (PSI) | Stop Pressure (PSI) | Stop 10 s Pressure (PSI) | Retention Delta (PSI) | Accuracy Delta (PSI) | Remarks |
|---|---|---|---|---|---|---|---|---|
| 1 | Mountain Bicycle | 0–15 | 15 | 15.8 | 15.2 | −0.60 | 0.20 | |
| 2 | Mountain Bicycle | 15–20 | 20 | 20.8 | 20.4 | −0.40 | 0.40 | |
| 3 | Mountain Bicycle | 20–25 | 25 | 25.8 | 25.2 | −0.60 | 0.20 | |
| 4 | Mountain Bicycle | 25–30 | 30 | 30.7 | 30.1 | −0.60 | 0.10 | |
| 5 | Mountain Bicycle | 30–35 | 35 | 35.6 | 35.2 | −0.40 | 0.20 | |
| 6 | Mountain Bicycle | 35–40 | 40 | 40.8 | 40.3 | −0.50 | 0.30 | |
| 7 | Mountain Bicycle | 40–45 | 45 | 45.8 | 45.2 | −0.60 | 0.20 | |
| 8 | Mountain Bicycle | 45–50 | 50 | 50.7 | 50.1 | −0.60 | 0.10 | |
| 9 | Mountain Bicycle | 50–55 | 55 | 55.8 | 55.1 | −0.70 | 0.10 | |
| 10 | Mountain Bicycle | 55–60 | 60 | 61.0 | 60.3 | −0.70 | 0.30 | |
| 11 | Mountain Bicycle | 0–60 | 60 | 60.7 | 60.3 | −0.40 | 0.30 |
Observations — Mountain Bicycle: All 11 mountain bike runs show tighter stop-pressure overshoot (+0.7 to +1.0 PSI) compared to road bike runs at equivalent presets. Retention delta is consistent at −0.40 to −0.70 PSI across the entire 15–60 PSI range. Accuracy delta is uniformly positive (0.10–0.40 PSI), meaning the final held pressure is always slightly above preset — an ideal outcome for safe inflation.
Conclusion
| Parameter | Road Bicycle Result | Mountain Bicycle Result |
|---|---|---|
| Unit Under Test | S3-1# | S3-1# |
| Preset Range Tested | 15–110 PSI | 15–60 PSI |
| Max Stop-Pressure Overshoot | +1.5 PSI (row 35, target 70 PSI) | +1.0 PSI (row 1, target 15 PSI) |
| Max Retention Loss (10 s) | −1.10 PSI | −0.70 PSI |
| Accuracy Delta Range | −0.30 to +1.00 PSI | +0.10 to +0.40 PSI |
| Positive Drift After Stop | None observed | None observed |
| Total Test Runs | 38 | 11 |
| Verdict | Pass | Pass |
Document Information
| Role | Name | Details |
|---|---|---|
| Tester | BTK | Recorded all pressure readings on 2025-06-30 |
| Source File | S3-精度测试-2025.6.30.xlsx | Sheet: S3-1#-自行车-山地车 (Index 2, Sheet 3 of 6) |
| Published By | Daniel Wright | ETENWOLF Test Lab |
Frequently Asked Questions
How accurate is the ETENWOLF S3 inflator when inflating bicycle tires?
In this test, the S3 Unit #1 stopped within +0.7 to +1.5 PSI above the preset target across all road and mountain bike runs. After a 10-second hold, the final reading was within −0.30 to +1.00 PSI of the preset for road bikes and +0.10 to +0.40 PSI for mountain bikes — well within normal consumer inflator tolerance.
Why does the pressure drop slightly after the inflator stops?
The small pressure drop observed during the 10-second hold (typically 0.4–1.1 PSI) is normal. It reflects air equalising through the check valve and hose as the system depressurises back toward the tire volume. It is not a sign of a tire leak.
Can the ETENWOLF S3 inflate both road bikes and mountain bikes accurately?
Yes. This report covers road bicycle presets from 15 to 110 PSI (38 test runs) and mountain bike presets from 15 to 60 PSI (11 test runs). Both tire types passed with consistent accuracy, with mountain bike runs showing slightly lower overshoot than road bike runs at comparable pressures.
What is the maximum preset pressure tested for the S3 on bicycle tires?
The maximum preset tested in this report is 110 PSI, using a road bicycle tire. All 110 PSI runs stopped between 110.0 and 111.3 PSI and held between 109.7 and 110.5 PSI after 10 seconds.
Related Products
Explore the full ETENWOLF S3 Cordless Tire Inflator product page for specifications, features, and purchasing information.
Additional accuracy test reports from the same S3 test series:
- S3-1# — Car Tire & Basketball: S3-1#-轿车-蓝球
- S3-2# — Car Tire & Basketball: S3-2#-轿车-蓝球
- S3-2# — Bicycle (Mountain Bike): S3-2#自行车-山地车
- S3-3# — Car Tire & Basketball: S3-3#-轿车-蓝球
- S3-3# — Bicycle (Mountain Bike): S3-3#-自行车-山地车