OS 0.75 piston ring kit designed specifically for the Honda TRX 420 Rancher family (2007–2013). This top-end refresh targets a bored cylinder to renew the piston-to-bore seal, restore compression, and reduce oil consumption without the expense or downtime of a full piston kit. Crafted as a precise aftermarket replacement, it brings factory-like performance back to dusty trails and demanding farm work. Over time, worn rings allow blow-by and power loss, especially in engines that spend long days under load in dirt and dust. This OS 0.75 kit re-establishes seal integrity between piston and bore, helping reclaim throttle response and long-term reliability for riders who rely on their Rancher for hard work and field duties.

Comprehensive Vehicle Fitment

Manufacturer	Models / Series	Years / Details
Honda	TRX 420 Rancher (TRX420 family including 4x4 and 2x4 variants)	2007–2013; 86.50 mm standard bore; OS +0.75 (87.25 mm) for top-end overbore
Honda	TRX 420 Rancher ES/Automatic and Manual variants	2007–2013; applicable to electric-start and manual transmissions across model lines
Honda	TRX 420 Rancher (All listed sub-models)	2007–2013; designed to fit standard 86.50 mm bore engines with oversize options

Notes: This compatibility reflects common TRX420 Rancher configurations used in farming and trail work during the 2007–2013 window. Always verify bore size on your specific machine before ordering.

Product Specifications

Attribute	Details
OEM Reference Part Numbers	13013-HP5-600
Type	Piston Ring Kit (oversize OS 0.75 mm)
Manufacturer	Aftermarket Replacement
Application	Honda TRX 420 Rancher, 2007–2013
Standard Bore	86.50 mm
Oversize	+0.75 mm (OS 0.75)
Actual Bore (Oversize)	87.25 mm
Ring Configuration	Top Compression Ring; Second Compression Ring; Oil Ring Assembly
Material	High-grade steel rings with wear-resistant coating
Notes	Includes rings only; piston, wrist pin, circlips, base gasket, and head gaskets are not included

OEM & Aftermarket Cross-Reference Information

Part Number	Brand / Type	Cross-Reference Notes
13013-HP5-600	Honda OEM	OS 0.75 piston ring kit; cross-reference with aftermarket options such as 13011-HP5-600
13011-HP5-600	Aftermarket Replacement	0.25 mm oversize alternative and standard cross-reference in many aftermarket catalogs
13012-HP5-600	Honda OEM	OS 0.50 oversize reference for TRX420 configurations
13010-HP5-600	Honda OEM / Aftermarket	Piston Rings used in related top-end kits; cross-reference in rebuild subsets

What’s Included

This kit includes the essential rings required to refresh one piston for the TRX 420 Rancher OS 0.75 application.

• Top Compression Ring
• Second Compression Ring
• Oil Ring Assembly

Note: Piston, wrist pin, circlips, base gasket, and cylinder head gaskets are not included.

Why Choose This Aftermarket Replacement?

• Direct-Fit Compatibility: Precisely engineered to match the TRX 420 Rancher bore and ring stack for a seamless top-end refresh.
• OEM Cross-Reference: Backed by accurate OEM references to ensure the correct oversize option for your model year.
• Premium Materials: High-grade steel rings with wear-resistant coatings designed for rugged trail and farm use.
• Performance Restoration: Restores compression and power without the downtime or cost of a full piston kit.
• Reliability Under Duress: Built to withstand dusty environments and hard use common to Rancher applications.
• Aftermarket Assurance: Engineered to meet or exceed OEM tolerances for longevity and consistent seal life.

Installation Notes:

• Inspect the bore for scoring and ensure it’s within service limits before installing the oversize rings.
• Confirm correct ring orientation and order; keep gaps staggered to minimize blow-by paths.
• Use a ring expander to avoid ringing or nicking corners when installing the compression rings.
• Apply clean engine oil to the rings and wipe the piston lands to prevent bonding or ring sticking.
• Check end gaps and rotate the piston to verify smooth ring seating before final assembly.
• Take care to clean all debris from the cylinder bore and ensure proper lubrication during initial startup.

Why Upgrade?

Worn piston rings on a TRX 420 Rancher lead to increased blow-by, reduced compression, and higher oil consumption. This OS 0.75 replacement restores sealing integrity, reclaiming power, throttle response, and long-term reliability without resorting to a full engine rebuild.

Note: Bore and oversize specifications reflect the intended OS 0.75 option for the TRX 420 Rancher 2007–2013 window, with bore sizing of 86.50 mm standard and 87.25 mm oversize when installed. These measurements align with documented 86.50 mm standard bores for the TRX420 platform and common oversize top-end practices, supporting a robust top-end refresh in dusty, field-use environments.