KB PERFORMANCE - KB425C.010 - Hypereutectic Piston Kit - '99-'06 Harley-Davidson Electra Glide Ultra Classic FLHTCU, Dyna 35th Anniversary Super Glide
This .010-over Hypereutectic Piston Kit fits '99-'06 Harley-Davidson engines being bored slightly oversize, machined by KB Performance from T-5 heat-treated 390 alloy to within a gram of weight and half a thousandth of an inch piston to piston. The precision allows a tighter fit than standard replacement pistons, improving ring seal and reducing piston rock, though KB's clearance and top ring end gap instructions should be followed closely. Includes two pistons, pins, spiral-lock clips, and Hastings moly rings; rings sold separately.
Features
- Manufactured from high-strength, T-5 heat-treated, 390 hypereutectic aluminum alloy
- Allows a tighter fit and longer piston and ring life
- Diamond-machined pistons are held to plus or minus one gram weight and less than one-half-thousandth-inch (.0005") tolerances from piston to piston
- Each kit contains two pistons, pins, spiral-lock pin clips and Hastings moly rings
- Replacement piston rings sold separately
- KB pistons can be installed tighter than other pistons. This results in less piston rock and better ring seal. Please read instructions included with piston for correct piston clearance.
- Due to the thermal conductivity and design of KB pistons, special attention is required to the top ring end gap. Please read instructions furnished with piston for correct ring installation.
Specs
- Compression Ratio: 8.8:1
- Displacement: 88"
- Riding Style: Street
- Ring Material: Moly Coated
- Bore Size: 3.750"
- Piston Head Shape: Flat Top
- Piston Material: Hypereutectic Alloy
- Stroke Length: 4.000"
- Units: Kit
- Product Name: Piston Kit
- Bore - Oversize: +0.010"
Frequently Asked Questions - KB PERFORMANCE - KB425C.010 - Hypereutectic Piston Kit - '99-'06 Harley-Davidson Electra Glide Ultra Classic FLHTCU, Dyna 35th Anniversary Super Glide
How do I know if this part fits my vehicle?
Check the fitment information listed on this page against your exact year, make, model, and (where applicable) trim, engine size, or configuration. If your exact vehicle isn't listed, or you're not sure, use the product chat on this page or contact our support team before ordering - we're glad to help confirm fitment.
What does it mean if a product is listed as universal fit?
Universal fit means the product is designed to work across a range of vehicles, not that it's guaranteed to fit every one. Compare the listed measurements, mounting requirements, and connector or hardware specs against your specific vehicle before ordering, since some installations may need additional hardware or minor fabrication.
Where can I find installation instructions for this product?
General installation notes are provided above where available. For detailed step-by-step instructions, refer to the manufacturer's documentation included with the product, or use the product chat on this page for questions about difficulty, required tools, or whether professional installation is recommended.
What if I have more questions about this product?
Use the product chat on this page for fitment, specs, installation, and compatibility questions, or contact our support team directly for help before you order.
