WISECO - 899M05400 - Piston Kit - Pro-Lite - 54.0 mm - YZ125

Q: Where can I find installation instructions for this product?

General installation notes are provided on the product page where available. For detailed step-by-step instructions, refer to the manufacturer's documentation included with the product, or use the product chat for questions about difficulty, required tools, or whether professional installation is recommended.

The WISECO 899M05400 is a Pro-Lite piston kit for 2022-2025 Yamaha YZ125 and YZ125X models, featuring a forged construction with Armorglide skirt coating that reduces wear and friction, plus forced pin oiling to improve small-end bearing and wrist-pin lubrication — includes piston rings, wrist pin, and circlips for a complete top-end replacement.

Features

Piston Kit includes a high-quality piston ring, high-strength wrist pin and circlips

Pro-lite Kit with drop-in, forged replacement optimizes greater strength-to-weight ratio over OEM part. Additional forced pin oiling improves small end bearing and wrist pin lubrication. Armorglide skirt coating reduces skirt and cylinder wear and improves performance through reduced operating friction. Offered in +2.00 mm overbore option for higher displacement builds

GP Series features forged material and offers increased tensile strength over OEM cast components and lightening operations result in approximately 7 g weight savings over OEM. Proprietary ArmorX coating in critical areas provides highly protective thermal barrier, reducing heat-induced damage and wear, and preventing ring microwelding. Shares the same Armorglide skirt coating and pin oiling benefits as Pro-lite

Specs

Product Name: Piston Kit

Style: Pro-Lite

Bore Size Metric: 54.00 mm

Engine Type: 2-Stroke

Units: Kit

Riding Style: Off-Road

Frequently Asked Questions - WISECO - 899M05400 - Piston Kit - Pro-Lite - 54.0 mm - YZ125 - '22-'25 Yamaha

General info

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.