{"product_id":"rk-racing-chain-gb420mxz-104-gold-heavy-duty-420-racing-chain","title":"RK Racing Chain GB420MXZ-104 Gold Heavy Duty 420 Racing Chain","description":"\u003cp\u003eIn this review the RK Racing Chain GB420MXZ-104 is evaluated for serious motocross riders who demand a light, strong non O-ring chain. The bottom line: this chain is built for performance-focused 50cc to 125cc open class racers because it pairs a high tensile strength with low weight, making it the clearest choice when durability under racing conditions and minimal rotating mass matter most. The review highlights construction, strength ratings, and real-world fit and appearance feedback to help riders decide if this is the right drivetrain upgrade.\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eChromoly construction:\u003c\/strong\u003e Chrome-moly steel rollers and bushings deliver a combination of strength and reduced weight that benefits acceleration and handling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOversized alloy pins:\u003c\/strong\u003e Special alloy pins are larger than typical pins to increase shear strength and resist bending in aggressive off-road use.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHIT heat treatment:\u003c\/strong\u003e All components are heat-treated with RK's HIT process to improve wear resistance and consistent performance lap after lap.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh tensile rating:\u003c\/strong\u003e The chain has a maximum tensile strength of 5000 ft-lb, giving confidence for professional-level racing demands.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLightweight:\u003c\/strong\u003e At about 1.76 lb for the 104-link length, it minimizes rotating mass for quicker throttle response on small-displacement race bikes.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThis chain is aimed at serious motocross racers and mechanics who run professional level 50cc to 125cc open class bikes and need a non O-ring chain that prioritizes strength and low weight. Track-focused riders who value a direct, low-maintenance chain with strong construction will find the GB420MXZ well suited to their needs.\u003c\/p\u003e\n\u003cp\u003eThose who should look elsewhere include riders who require O-ring lubrication for longer service intervals, casual riders who prioritize convenience over peak performance, or machines outside the recommended displacement range where a different series would better match load and wear expectations.\u003c\/p\u003e\n\u003ch2\u003ePros \u0026amp; Cons\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003ePros\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eExceptional strength for its class with a 5000 ft-lb tensile rating that supports aggressive riding and racing.\u003c\/li\u003e\n\u003cli\u003eLow weight at 1.76 lb for reduced rotational mass and improved throttle response on small-displacement race bikes.\u003c\/li\u003e\n\u003cli\u003eDurable construction with chrome-moly components, seamless rollers and oversized pins, plus HIT heat treatment for wear resistance.\u003c\/li\u003e\n\u003cli\u003eAttractive gold finish and good fitment reported by riders, offering both looks and function.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eNon O-ring design means more frequent maintenance compared with O-ring chains if long wear life between services is desired.\u003c\/li\u003e\n\u003cli\u003eSpecifically optimized for 50cc to 125cc open class racing, so it may not be ideal for larger displacement or street-focused applications.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eSeries\u003c\/td\u003e\n\u003ctd\u003eGB420MXZ (420 Series)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLink count\u003c\/td\u003e\n\u003ctd\u003e104 links\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePin length\u003c\/td\u003e\n\u003ctd\u003e15.7 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum tensile\u003c\/td\u003e\n\u003ctd\u003e5000 pounds\/ft\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e1.76 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaster link type\u003c\/td\u003e\n\u003ctd\u003eClip\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWear life index\u003c\/td\u003e\n\u003ctd\u003e300\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch2\u003eOur Verdict\u003c\/h2\u003e\n\u003cp\u003eThe GB420MXZ-104 is a focused racing chain that delivers industry-leading strength and low weight for 50cc to 125cc open class racers, representing strong value for riders who maintain their drivetrain and prioritize performance. Its chromoly build, oversized pins and HIT heat treatment make it a sensible upgrade for competitive motocross, while riders wanting longer service intervals or street convenience should consider O-ring options instead.\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eIs this chain suitable for 50cc to 125cc race bikes?\u003c\/strong\u003e\u003cbr\u003eYes. The GB420MXZ is specifically designed for professional level 50cc to 125cc open class racing and balances strength with low weight for those machines.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes the chain come with a master link type?\u003c\/strong\u003e\u003cbr\u003eThe chain uses a clip-style master link, which is standard for many race chains and allows for secure connection and straightforward installation.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow durable is the gold finish and construction?\u003c\/strong\u003e\u003cbr\u003eCustomers report the gold finish looks great and the chromoly construction with HIT heat treatment provides strong durability, though as a non O-ring chain it requires regular maintenance for best wear life.\u003c\/p\u003e","brand":"RK Racing Chain","offers":[{"title":"Default Title","offer_id":48612542283995,"sku":"B0022UOAMA","price":33.23,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/61ix4ac5POL._AC_SL1000_f56821dc-0978-4226-8b17-bc9288523443.jpg?v=1778371401","url":"https:\/\/gearmusthave.com\/products\/rk-racing-chain-gb420mxz-104-gold-heavy-duty-420-racing-chain","provider":"GearMustHave","version":"1.0","type":"link"}