{"product_id":"cylinder-barrel-kit-125cc-piston-gaskets-egr-01242-eng-aft","title":"K157FMI 125cc 57mm Cylinder Barrel \u0026 Piston Kit – EGR Type","description":"\u003ch2\u003eK157FMI 125cc 57 mm Cylinder Barrel \u0026amp; Piston Kit\u003c\/h2\u003e\u003cp\u003eBrand-new unbranded standard-bore top-end rebuild kit for selected air-cooled K157FMI \/ 157FMI GS-style 125cc engines using the matching 57 mm EGR\/secondary-air-system cylinder configuration.\u003c\/p\u003e\u003ch3\u003eKey Specifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eEngine family: K157FMI \/ 157FMI GS-style\u003c\/li\u003e\n\u003cli\u003eDisplacement: Standard 125cc application\u003c\/li\u003e\n\u003cli\u003eStandard bore: 57 mm\u003c\/li\u003e\n\u003cli\u003eEngine stroke reference: 48.8 mm\u003c\/li\u003e\n\u003cli\u003ePiston-pin reference: 14 mm\u003c\/li\u003e\n\u003cli\u003eCooling: Air-cooled\u003c\/li\u003e\n\u003cli\u003eEngine type: Single-cylinder 4-stroke\u003c\/li\u003e\n\u003cli\u003eCylinder style: EGR \/ secondary-air-system type\u003c\/li\u003e\n\u003cli\u003eCondition: Brand new\u003c\/li\u003e\n\u003cli\u003eType: Unbranded aftermarket replacement\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eWhat's Included\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e1 x cylinder barrel\u003c\/li\u003e\n\u003cli\u003e1 x piston\u003c\/li\u003e\n\u003cli\u003e1 x piston ring set\u003c\/li\u003e\n\u003cli\u003eHead and base gaskets\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eVehicle \/ Engine Compatibility\u003c\/h3\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eMake\u003c\/th\u003e\n\u003cth\u003eModel \/ Engine\u003c\/th\u003e\n\u003cth\u003eYears \/ Scope\u003c\/th\u003e\n\u003cth\u003eNotes\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eLexmoto\u003c\/td\u003e\n\u003ctd\u003eAdrenaline 125 \/ Adrenaline 125 EFI\u003c\/td\u003e\n\u003ctd\u003eK157FMI 57 x 48.8 mm engine family\u003c\/td\u003e\n\u003ctd\u003eVerify EGR ports and original cylinder\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLexmoto\u003c\/td\u003e\n\u003ctd\u003eValiant 125 \/ Valiant 125 EFI\u003c\/td\u003e\n\u003ctd\u003eK157FMI 57 x 48.8 mm engine family\u003c\/td\u003e\n\u003ctd\u003eVerify EGR ports and original cylinder\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSinnis\u003c\/td\u003e\n\u003ctd\u003eApache \/ Blade \/ Cafe \/ Max 2 \/ Retrostar \/ Scrambler \/ Stealth \/ Trackstar \/ Vista 125\u003c\/td\u003e\n\u003ctd\u003eK157FMI applications\u003c\/td\u003e\n\u003ctd\u003eModel-year and emissions specification vary\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePulse \/ Superbyke\u003c\/td\u003e\n\u003ctd\u003eAdrenaline 125 \/ RMR125\u003c\/td\u003e\n\u003ctd\u003eK157FMI applications\u003c\/td\u003e\n\u003ctd\u003eMatch original cylinder and EGR arrangement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eAdditional Verified Keeway Applications\u003c\/h3\u003e\u003cp\u003eThe following Keeway applications use the same documented 57 mm \/ 14 mm GS-style top-end family. Engine suffixes and OEM cylinder revisions vary, so the original cylinder and EGR\/secondary-air ports must still be compared before ordering.\u003c\/p\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eKeeway Model\u003c\/th\u003e\n\u003cth\u003eYears \/ Variant\u003c\/th\u003e\n\u003cth\u003eFitment Notes\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eRKS 125 \/ RKS Classic\u003c\/td\u003e\n\u003ctd\u003e2011–2017\u003c\/td\u003e\n\u003ctd\u003e157FMI-2B \/ GS-style 57 x 48.8 mm family; OEM cylinder 139013210030 on Euro 3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRKS 125 EFI \/ RKS Sport EFI\u003c\/td\u003e\n\u003ctd\u003e2017–2020 verified\u003c\/td\u003e\n\u003ctd\u003e57 mm piston \/ 14 mm pin family; later OEM cylinder revisions exist\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRKV 125\u003c\/td\u003e\n\u003ctd\u003e2011–2016\u003c\/td\u003e\n\u003ctd\u003e57 mm piston \/ 14 mm pin; OEM cylinder family 139013210030\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRKV 125 EFI \/ CBS EFI\u003c\/td\u003e\n\u003ctd\u003e2017–2023 catalogued\u003c\/td\u003e\n\u003ctd\u003e57 mm piston \/ 14 mm pin family; compare original cylinder revision\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTX 125 Enduro \/ Supermoto\u003c\/td\u003e\n\u003ctd\u003e2009–2017\u003c\/td\u003e\n\u003ctd\u003e157FMI-2B, 57 x 48.8 mm; OEM cylinder 139013210030\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTX 125 EFI Enduro \/ Supermoto\u003c\/td\u003e\n\u003ctd\u003e2018–2020\u003c\/td\u003e\n\u003ctd\u003e57 mm piston \/ 14 mm pin family; compare EGR\/SLS ports\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStrike 125\u003c\/td\u003e\n\u003ctd\u003e2013–2014 documented\u003c\/td\u003e\n\u003ctd\u003eExplicitly catalogued as K157FMI; OEM cylinder 139013210030 and piston 179133090003\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eImportant Fitment Information\u003c\/h3\u003e\u003cp\u003eThe K157FMI engine family is well documented at 57 mm bore x 48.8 mm stroke, but not every K157FMI installation uses an identical cylinder or emissions arrangement. Check the EGR\/secondary-air fittings and all physical dimensions against the existing parts before ordering.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo not order by 125cc capacity alone.\u003c\/strong\u003e Before purchase, compare the original engine code, 57 mm bore, piston-pin diameter, piston crown\/profile, cylinder height, stud spacing, gasket profile, oil passages and EGR\/secondary-air ports with the existing engine.\u003c\/p\u003e\u003cp\u003eThe K157FMI family was used across carburetted and fuel-injected motorcycles, and production changes can affect top-end components. This kit should only be used where the original parts match the standard 57 mm K157FMI EGR-style configuration.\u003c\/p\u003e\u003ch3\u003eInstallation\u003c\/h3\u003e\u003cp\u003eCorrect piston-ring orientation, piston direction, valve timing, gasket installation and cylinder-head torque are essential. Professional installation is recommended where the correct engine-building procedure is not known.\u003c\/p\u003e","brand":"Unbranded","offers":[{"title":"Default Title","offer_id":57499555430775,"sku":"01242-ENG","price":44.0,"currency_code":"SHP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0528\/8771\/6007\/files\/20260929_113018.jpg?v=1790772653","url":"https:\/\/www.motomaniauk.com\/products\/cylinder-barrel-kit-125cc-piston-gaskets-egr-01242-eng-aft","provider":"Moto Mania UK","version":"1.0","type":"link"}