{"product_id":"dhm-gen-2-high-compression-piston-kit-for-2014-2020-grom-2019-2021-monkey","title":"DHM Gen 2 High Compression Piston Kit for 2014-2020 Grom \/ 2019-2021 Monkey","description":"\u003ch2\u003eDHM Gen 2 High Compression Stock Bore Piston Kit\u003c\/h2\u003e\n\u003cp\u003eThe DH Motoring Gen 2 piston kit combines a 52.4mm stock bore with approximately 13.2:1 compression for a race-focused 125cc engine build. Its exclusive high-compression dome, enlarged oiling passages and 360-degree skirt are designed to support lubrication and strength during extended high-RPM use.\u003c\/p\u003e\n\u003ch3\u003eRace-developed design\u003c\/h3\u003e\n\u003cp\u003eDeveloped from six years of DH Motoring racetrack testing with more than a dozen stock bore piston designs, this kit targets increased lubrication while pushing compression for pump fuel. DH Motoring reports that its race-spec design has produced more horsepower than any other stock bore kit it tested and describes it as the highest-compression stock bore piston on the market. The dome is made exclusively for DH Motoring.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eEnlarged ring and skirt oiling holes feed the oil spring channel and skirt to support lubrication across the RPM range.\u003c\/li\u003e\n\u003cli\u003eA larger oil spring increases oil volume between the oiling rings.\u003c\/li\u003e\n\u003cli\u003eOil ports beneath the pin holes help keep the wrist pin lubricated.\u003c\/li\u003e\n\u003cli\u003eA 360-degree skirt design increases overall strength.\u003c\/li\u003e\n\u003cli\u003eValve reliefs accommodate cylinder head valves up to 27.5\/23.5mm. DH Motoring states that the relief depth was designed for compatibility with high-lift cams.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eSpecifications and included parts\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eBore: 52.4mm, stock bore.\u003c\/li\u003e\n\u003cli\u003eCompression ratio: approximately 13.2:1.\u003c\/li\u003e\n\u003cli\u003eGeneration: Gen 2.\u003c\/li\u003e\n\u003cli\u003eIncludes racing piston ring kit, pins and circlips.\u003c\/li\u003e\n\u003cli\u003eIncludes new base and head gaskets.\u003c\/li\u003e\n\u003cli\u003eCylinder is not included; this listing is for the piston kit.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eApplication and spark plug options\u003c\/h3\u003e\n\u003cp\u003eListed for 2014–2020 Honda Grom \/ Monkey applications. Confirm your specific model and engine configuration before installation.\u003c\/p\u003e\n\u003cp\u003eChoose the piston kit without a spark plug or add an NGK CR9E spark plug using the existing option.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eRequires an NGK CR9E (6263) spark plug.\u003c\/li\u003e\n\u003cli\u003eRequires fuel rated at least 91 octane.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eInstallation and piston ring end gaps\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eInstalling this piston requires setting the ring gaps. If you are not comfortable with this, have your local shop perform the installation. Failure to set the proper piston ring end gap can result in premature failure or engine seizure.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eRecommended top ring end gap: .007–.009 inches.\u003c\/li\u003e\n\u003cli\u003eRecommended bottom ring end gap: .009–.011 inches.\u003c\/li\u003e\n\u003cli\u003eThe silver ring goes on top; the black ring goes below.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eUnknown Overland explains the ring-gap procedure in the installation video below.\u003c\/p\u003e\n\u003cp\u003e\u003ciframe src=\"https:\/\/www.youtube.com\/embed\/LlQNSwmadaA\" height=\"315\" width=\"560\"\u003e\u003c\/iframe\u003e\u003c\/p\u003e","brand":"DH Motoring","offers":[{"title":"No","offer_id":67474043273457,"sku":"PK-001","price":120.0,"currency_code":"USD","in_stock":true},{"title":"Yes","offer_id":67474043306225,"sku":"sku-32783387557991","price":131.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0626\/1348\/7857\/files\/IMG_2304.jpg?v=1794186675","url":"https:\/\/howlingmoto.com\/products\/dhm-gen-2-high-compression-piston-kit-for-2014-2020-grom-2019-2021-monkey","provider":"Howling Moto","version":"1.0","type":"link"}