Dedicated Subsystem WorkbenchPlatform Gen: 2017–2026

2025 Harley Davidson Street Glide (Milwaukee-Eight) Cylinder Compression & Leakdown Diagnostic Engine

Factory compression specs for 2025 Harley Davidson Street Glide (Milwaukee-Eight): standard pressure 180 - 225 PSI (1241 - 1551 kPa), service limit 140 PSI, dry vs wet test diagnostics and acoustic leak stethoscope.

Gen 2017–2026

Factory Platform Compatibility: All workshop fluid capacities, maintenance milestones, torque specifications, and consumables on this specification sheet are factory-identical across model years 2017 through 2026.

Select Model Year:(Active: 2025)

2017 2018 2019 2020 2021 2022 2023 2024 2025 2026

Engine

1746cc

Drive

Chain

Cooling

Precision Air/Oil-Cooled

Cylinder Compression & Leakdown Diagnostic Engine

Multi-Cylinder Dry vs. Wet Test Bench, Differential Pressure Regulator & Acoustic Stethoscope Locator

Ratio: 10.2:1Std: 180-225 PSILimit: 140 PSIWhip Adapter: M10 x 1.25

Automatic Compression Release (ACR) Solenoids

M8 heads utilize ECU-controlled electronic ACR solenoids in spark plug wells. Disconnect ACR harness plugs during compression testing to measure true mechanical cylinder pressure, or readings will register 30-40 PSI below actual.

Diagnostic Presets:

Cyl #1 (Front)IN-SPEC

209PSI(1441 kPa)

Cyl #2 (Rear)IN-SPEC

207PSI(1427 kPa)

Cross-Cylinder Variance: Δ 2 PSI (OEM Limit: ≤ 15 PSI)

VARIANCE IN-SPEC

All cylinders demonstrate strong, balanced mechanical sealing. Piston ring packs, cylinder cross-hatch, and valve seats are within factory specification.

Official Workshop Manual Compression Test Protocol

Step 0 of 5 Completed

Step 1: Engine Operating Temperature

Run engine until coolant reaches 60°C - 80°C (140°F - 176°F). Cylinder expansion brings rings and pistons to true operating clearances.

Step 2: Spark Plug Removal & Port Clean

Blow compressed air around spark plug wells to eject grit, then remove all spark plugs. Thread in M10 x 1.25 whip adapter hand-tight with fresh O-ring.

Step 3: Wide-Open Throttle (WOT) Lock

Hold throttle grip fully wide open (or lock throttle bodies open) to eliminate intake butterfly vacuum restriction and ensure 100% volumetric cylinder filling.

Step 4: Battery Tender Voltage Stabilization

Connect a 12V shop battery tender or booster. Starter must sustain uninterrupted cranking speed (300 RPM) to build maximum dynamic stroke pressure.

Step 5: Crank 4-6 Compression Strokes

Engage starter until gauge needle ceases rising (typically 4 to 6 strokes). Record maximum peak pressure and compare against the OEM limits above.

Official NHTSA Safety Recalls & Technical Bulletins

0 Open Campaigns (Clean)

U.S. Department of Transportation compliance database (Title 49 U.S.C. Chapter 301).

Verify VIN on NHTSA.gov

No Active Federal Safety Recalls Reported

The U.S. DOT National Highway Traffic Safety Administration (NHTSA) records zero open safety recall campaigns for the 2025 Harley Davidson Street Glide (Milwaukee-Eight) platform. Always check your individual 17-digit VIN at an authorized dealership or via NHTSA.gov for individual recall completions.