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Replace your damaged or worn OEM cylinderMade from cast aluminum; nickel silicon carbide platedPrecision-machined and honed to OEM stock bore sizesExtremely durable low-friction bore surface allows for greater heat dissipationStock OEM appearanceMade in...

Replace your damaged or worn OEM cylinderMade from cast aluminum; nickel silicon carbide platedPrecision-machined and honed to OEM stock bore sizesExtremely durable low-friction bore surface allows for greater heat dissipationStock OEM appearanceMade in...

Ideal engine part to complete Koso's big bore kitUnique four-valve design increases air flow and performanceProvides more power and torqueFeatures a forged piston, stainless steel 24 mm intake valves and 20 mm exhaust valves Honda -- MSX125 Grom --...

Big Bore Cylinder Kit - 150 Cc - Honda Grom/Monkey Mb640000 Honda -- Z125M Monkey ABS -- (2022); Honda -- MSX125 Grom -- (2022); Honda -- Z125M Monkey -- (2022); Honda -- MSX125 Grom ABS -- (2022)

Stainless steel conversion kits include only what?s needed to convert your head to the long-life stainless steel Black Diamond intake valvesExtend the life of the valve train and intake components by as much as 4x over the OEM titanium partsValves are...

Contact surfaces designed for improved sealingHigh-temperature Viton? and PTFE materialsImproved tolerance over OEM100% quality controlledKits include one full set of intake and exhaust sealsMade in the USA KTM -- 450 XC-W -- (2012, 2010, 2011, 2009,...

Stainless steel conversion kits include only what?s needed to convert your head to the long-life stainless steel Black Diamond intake valvesExtend the life of the valve train and intake components by as much as 4x over the OEM titanium partsValves are...

Contact surfaces designed for improved sealingHigh-temperature Viton? and PTFE materialsImproved tolerance over OEM100% quality controlledKits include one full set of intake and exhaust sealsMade in the USA KTM -- 250 RC4 -- (2008); KTM -- 250 SXS-F --...

Stainless steel conversion kits include only what?s needed to convert your head to the long-life stainless steel Black Diamond intake valvesExtend the life of the valve train and intake components by as much as 4x over the OEM titanium partsValves are...

Contact surfaces designed for improved sealingHigh-temperature Viton? and PTFE materialsImproved tolerance over OEM100% quality controlledKits include one full set of intake and exhaust sealsMade in the USA Yamaha -- YZ 250 F -- (2020, 2019)

Stainless steel conversion kits include only what?s needed to convert your head to the long-life stainless steel Black Diamond intake valvesExtend the life of the valve train and intake components by as much as 4x over the OEM titanium partsValves are...

Stainless steel conversion kits include only what?s needed to convert your head to the long-life stainless steel Black Diamond intake valvesExtend the life of the valve train and intake components by as much as 4x over the OEM titanium partsValves are...