OEM Harley Ironhead Sportster 900 Front Cylinder 16561-57 – 3.04 in / +.040

Genuine Harley-Davidson 900cc Ironhead Sportster front cylinder with the 16561-57 casting family. The bore measures approximately 3.04 inches.

Part Number / Markings: 16561-57 (inventory shorthand was 656-57)
Condition: Used – machine-shop inspection recommended

USED PARTS DISCLAIMER: This is a used motorcycle part and may show normal signs of age, installation, removal, storage, and previous use including scratches, scuffs, discoloration, surface corrosion, paint loss, or other cosmetic wear. Any known damage or defects are noted when known. Unless otherwise stated, the photos show the actual item being sold and are considered part of the description.

BORE / IDENTIFICATION: Measured 3.04 in. Factory 900cc Ironhead bore is 3.000 in, making this approximately +.040 in oversize.

FITMENT NOTES: The 3.04-inch measurement is consistent with a 900cc Ironhead cylinder bored approximately .040 over the 3.000-inch factory bore. Verify the full casting, bore taper, out-of-round, fins, threads, base flange, and gasket surfaces.

FITMENT: Buyer is responsible for verifying fitment before purchasing. Fitment information is provided as a reference based on available part numbers, casting marks, measured dimensions, donor information, and published references. Motorcycles may have been modified over time. Compare the part number, casting, mounting points, bore, dimensions, electrical connections, and photos with the part currently on your motorcycle.

QUESTIONS? Send us a message before purchasing if you need additional measurements, photos, condition details, or clarification on what is included.

SHIPPING: Orders are typically processed and shipped within 1–2 business days after payment. Tracking is provided once the order ships. Parts are packed according to size, weight, and type. Large, heavy, or oversized items may require additional handling or shipping arrangements.