Common Harley-Davidson Engine Capacities (Milwaukee-Eight Era)

• 107ci (1750cc) — Entry-level stock (e.g., many Touring models; ~80–90 hp / ~100–110 ft-lb torque stock).
• 114ci (1868cc) — Common high-output stock (e.g., most modern Softails/Tourings; ~90–100 hp / ~110–120 ft-lb torque stock).
• 117ci (1923cc) — Factory high-performance stock (e.g., CVO models or later upgrades; ~100–110 hp / ~120–125 ft-lb torque).
• 121ci / 122ci — Aftermarket/Stage kits (e.g., some high-output variants or early big-bore builds; ~110–125 hp).
• 128ci — Advanced Stage kits (e.g., 4.31" bore × 4.375" stroke combos; 120+ hp potential).
• 131ci (2151cc) — The top-tier shown here (4.31" bore × 4.5" stroke; 121–124 hp / 130–135 ft-lb standard, up to 140–150+ hp with custom tuning/exhaust in some builds).

These larger displacements come from bigger bores, longer strokes, high-compr