The Stage II Big Bore Kit provides the parts you need to increase the horsepower of your EFI-equipped model. The kit increases the displacement of your Twin Cam-equipped model from 96 cubic inches (1584cc) to 103 cubic inches (1690cc).
- Black highlighted
- Includes big bore cylinders, big bore flat top pistons and rings, SE-255 cams, stage I air cleaner kit with one-piece back plate, top end gasket kit, and heavy duty clutch spring
- Separate purchase of cam spacers is recommended
- Requires separate purchase of primary cover gasket
- All EFI-equipped models require dealer-installed ECM calibration download or use of tunable Screamin' Eagle® Street Tuner Kit (priced separately)
- California kits are street compliant on California pollution controlled vehicles when used with Original equipment mufflers
- Recalibration is required for proper installation, See Dealer for details, Labor cost not included
- When installed by an authorized Harley-Davidson Dealer within 60-days of the vehicle purchase, compliant kits do not impact the vehicle's limited warranty
Dealer Install RecommendedYes
Warranty1 year limited warranty – Go to www.h-d.com/warranty for full details
Requires ECM CalibrationYes
Sold in UnitEach
In The BoxBig bore cylinders, big bore flat top pistons and rings, SE-255 cams, stage I air cleaner kit with one-piece back plate, top end gasket kit, and heavy duty clutch spring
Sold SeparatelyCam spacers and primary cover gasket
Upgrade Stage LevelStage III
Fits 49-State ’09 Touring models. Kit includes catalyst head pipe. Does not fit Trike models. Not street compliant in California. Installation requires separate purchase of Primary Cover Gasket. Cam Drive Retention Kit P/N 25566-06. Cam Spacer Kit P/N 25928-06 is recommended. All models require ECM calibration for proper installation.
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- Harley-Davidson® motorcycles modified with some performance engine parts must not be used on public roads and, in some cases, may be restricted to closed-course competition. Those performance parts identified with a stop hand symbol are U.S. EPA legal, but are NOT legal for sale or use in California on pollution-controlled motor vehicles. California guidelines on tampering can also lead to substantial fines and penalties.
Installation of automatic or manual compression releases on large displacement engines is highly recommended.
Installation of California performance kit onto a 49-state model motorcycle or a 49-state performance kit on a California model motorcycle will void manufacturers warranty, as it will not result in a street compliant configuration.
Q & A
what is compression rate with these kit head gaskets
Please Hold Your Iron Horses