{"product_id":"piston-kit-honda-trx-300-os-1-00-1988-2000","title":"Piston Kit OS 0.50 For Honda TRX 300 ATV 1988 2000 Fits 2X4 And 4X4 Models OEM Replacement","description":"\u003cdiv\u003e\n\u003cp\u003eThis OS 0.50 oversize piston kit is designed for top-end rebuilds on the Honda TRX 300 SporTrax family, spanning model years 1988 through 2000 and covering both 2x4 and 4x4 configurations. Replacing the worn bore, rings, and piston with an oversize kit restores compression and power, delivering dependable performance whether you’re tearing up the trail or tackling rugged farm chores. Engineered to tight tolerances, this kit provides a durable, repeatable rebuild solution that keeps your TRX 300 punching above its weight day after day.\u003c\/p\u003e\n\u003cp\u003eThe aftermarket piston kit delivers a complete top-end replacement that addresses common wear-and-tear problems such as bore wall wear, ring fracture, and piston skirt scuffing. With a complete set that includes the piston, rings, wrist pin, and circlips, it’s a reliable, cost-effective option for restoring engine performance in the field—whether you’re on a remote trail or working a utility route.\u003c\/p\u003e\n\u003ch3\u003eComprehensive Vehicle Fitment\u003c\/h3\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eManufacturer\u003c\/th\u003e\n\u003cth\u003eModels \/ Series\u003c\/th\u003e\n\u003cth\u003eYears \/ Details\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eHonda\u003c\/td\u003e\n\u003ctd\u003eTRX 300 SporTrax (2x4 \/ 4x4)\u003c\/td\u003e\n\u003ctd\u003e1988–2000\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cem\u003eSource: Honda TRX 300 fitment data showing 1988–2000 coverage for the SporTrax platform.\u003c\/em\u003e\u003c\/p\u003e\n\u003ch3\u003eProduct Specifications\u003c\/h3\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eAttribute\u003c\/th\u003e\n\u003cth\u003eDetails\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOEM Reference Part Numbers\u003c\/td\u003e\n\u003ctd\u003e13105-HC4-305; related variants seen in the market include 13105-HM3-670, 13104-HM3-670, 13103-HM3-670, 13102-HM3-670, 13101-HM3-670\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType\u003c\/td\u003e\n\u003ctd\u003ePiston Kit (OS 0.50 oversize)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eManufacturer\u003c\/td\u003e\n\u003ctd\u003eAftermarket Replacement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApplication\u003c\/td\u003e\n\u003ctd\u003eHonda TRX 300 (1988–2000) top-end rebuilds\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003eAluminum alloy piston with precision-machined rings\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOversize\u003c\/td\u003e\n\u003ctd\u003e0.50 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIncludes\u003c\/td\u003e\n\u003ctd\u003ePiston, rings, wrist pin, circlips\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003e\u003c\/h3\u003e\n\u003ch3\u003eOEM \u0026amp; Aftermarket Cross-Reference Information\u003c\/h3\u003e\n\u003ctable style=\"width: 100%;\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth style=\"width: 21.4801%;\"\u003ePart Number\u003c\/th\u003e\n\u003cth style=\"width: 14.4192%;\"\u003eBrand \/ Type\u003c\/th\u003e\n\u003cth style=\"width: 63.3787%;\"\u003eCross-Reference Notes\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"width: 21.4801%;\"\u003e13105-HC4-305\u003c\/td\u003e\n\u003ctd style=\"width: 14.4192%;\"\u003eOEM\u003c\/td\u003e\n\u003ctd style=\"width: 63.3787%;\"\u003eOriginal Honda piston reference for TRX 300; OS 0.50 variant available through aftermarket channels\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"width: 21.4801%;\"\u003e13105-HM3-670\u003c\/td\u003e\n\u003ctd style=\"width: 14.4192%;\"\u003eOEM\u003c\/td\u003e\n\u003ctd style=\"width: 63.3787%;\"\u003eCommon cross-reference variant used on TRX 300 engine families\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"width: 21.4801%;\"\u003e13104-HM3-670\u003c\/td\u003e\n\u003ctd style=\"width: 14.4192%;\"\u003eOEM\u003c\/td\u003e\n\u003ctd style=\"width: 63.3787%;\"\u003eCross-reference variant used on related TRX 300 engines\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"width: 21.4801%;\"\u003e13103-HM3-670\u003c\/td\u003e\n\u003ctd style=\"width: 14.4192%;\"\u003eOEM\u003c\/td\u003e\n\u003ctd style=\"width: 63.3787%;\"\u003eCross-reference variant used on related TRX 300 engines\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"width: 21.4801%;\"\u003e13102-HM3-670\u003c\/td\u003e\n\u003ctd style=\"width: 14.4192%;\"\u003eOEM\u003c\/td\u003e\n\u003ctd style=\"width: 63.3787%;\"\u003eCross-reference variant used on related TRX 300 engines\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"width: 21.4801%;\"\u003e13101-HM3-670\u003c\/td\u003e\n\u003ctd style=\"width: 14.4192%;\"\u003eOEM\u003c\/td\u003e\n\u003ctd style=\"width: 63.3787%;\"\u003eCross-reference variant used on related TRX 300 engines\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003e\u003c\/h3\u003e\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cp\u003eThis kit ships as a complete top-end replacement with all components needed for a serviceable install. In the box you’ll find:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cb\u003ePiston\u003c\/b\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003cb\u003ePiston Rings\u003c\/b\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003cb\u003eWrist Pin\u003c\/b\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003cb\u003eCirclips\u003c\/b\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003eNote: Related gaskets, seals, or other ancillary hardware are not included unless specified.\u003c\/em\u003e\u003c\/p\u003e\n\u003ch3\u003eWhy Choose This Aftermarket Replacement?\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cb\u003eDirect-Fit Compatibility:\u003c\/b\u003e Precisely matched to the TRX 300 bore and mounting interfaces for a straightforward installation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eOEM Cross-Reference:\u003c\/b\u003e Backed by established OEM cross-references to support proper selection across model years.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003ePremium Materials:\u003c\/b\u003e High-quality aluminum alloy piston designed for reliable heat management and strength under load.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003ePerformance Restoration:\u003c\/b\u003e Oversize 0.50 mm increases displacement enough to restore compression and throttle response after bore wear.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eComprehensive Kit:\u003c\/b\u003e Includes piston, rings, wrist pin, and circlips for a complete top-end rebuild.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eCost-Effective Reliability:\u003c\/b\u003e A durable aftermarket option that revives power without OEM pricing, ideal for trail and farm use.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eInstallation Notes:\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eVerify cylinder bore condition and measure for wear; if bore wear exceeds service limits, perform the appropriate honing or bore repair before installing the oversize kit.\u003c\/li\u003e\n\u003cli\u003eClean all components thoroughly; degrease the bore and oil passages to prevent debris from scoring the new piston rings.\u003c\/li\u003e\n\u003cli\u003eOrient the piston correctly to the engine’s intake\/exhaust ports and use fresh assembly lubricant on the skirt and rings during install.\u003c\/li\u003e\n\u003cli\u003eInstall the piston rings with gaps staggered (typically 120 degrees apart) and ensure they seat evenly against the ring lands.\u003c\/li\u003e\n\u003cli\u003eInsert the wrist pin with the circlips seated fully in their grooves; verify clips are fully installed and not protruding into the bore.\u003c\/li\u003e\n\u003cli\u003eReassemble using proper torque specs for any retained components and perform a careful break-in procedure as recommended for top-end rebuilds.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eWhy Upgrade?\u003c\/h3\u003e\n\u003cp\u003eRunning a worn or mismatched piston kit in a TRX 300 can lead to loss of compression, reduced power, and irregular fueling, especially under load on trails or farm work. This OS 0.50 oversize replacement restores compression and throttle response, delivering dependable, repeatable performance and extending the engine’s useful life.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"ATV City","offers":[{"title":"Default Title","offer_id":57319258882422,"sku":"190.10002-4","price":74.67,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0971\/0302\/0406\/files\/image_2026-02-25_232750524.png?v=1774886125","url":"https:\/\/dgtagri.co.uk\/products\/piston-kit-honda-trx-300-os-1-00-1988-2000","provider":"DGT Agri","version":"1.0","type":"link"}