{"product_id":"primary-clutch-spring-120-310-sku-05-120-310","title":"Primary Clutch Spring (120-310) \/\/ SKU: 05-120-310","description":"\u003ch3\u003ePrimary Drive Clutch Spring (120-310) \/\/ SKU: 05-120-310\u003c\/h3\u003e\n\u003cp\u003eFine-tune your clutch engagement and maintain consistent peak operating RPM under heavy load with the Bikeman Performance \u003cb\u003e120-310 Primary Clutch Spring\u003c\/b\u003e. As a core component of your drive clutch tuning, the primary spring directly governs engagement speed, upshift timing, and peak RPM retention across your powerband.\u003c\/p\u003e\n\u003cp\u003eFeaturing a \u003cb\u003e120 lb initial load and a 310 lb finish load\u003c\/b\u003e, this spring profile delivers smooth, predictable engagement to prevent belt slap or aggressive trenching off the line, while the stiff 310 lb finish rate holds target operating RPM without fading during long, full-throttle pulls. Precision-manufactured from high-tensile spring steel, it resists heat sag and rate degradation over severe operating conditions.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003eKey Performance Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003e120-310 Spring Rate Curve:\u003c\/b\u003e 120 lb initial rate ensures smooth, controlled clutch engagement; 310 lb finish rate maintains firm side pressure at full shift-out.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eHolds Target Shift RPM:\u003c\/b\u003e Prevents RPM drop and engine loading fade under heavy horsepower, deep snow, or steep hill-climbing conditions.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eHigh-Tensile Alloy Construction:\u003c\/b\u003e Engineered to withstand rapid compression cycles, extreme under-hood temperatures, and high torsional stress without losing spring rate over time.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eVersatile Tuning Component:\u003c\/b\u003e Ideal for pairing with stock or aftermarket adjustable clutch weights to tailor clutch calibration to specific tracks, tires, or power mods.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003eProduct Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eSKU:\u003c\/b\u003e 05-120-310\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eInitial Load:\u003c\/b\u003e 120 lbs\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eFinish Load:\u003c\/b\u003e 310 lbs\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eComponent Type:\u003c\/b\u003e Primary Drive Clutch Spring\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003ePrimary Function:\u003c\/b\u003e Manages drive clutch engagement RPM, upshift force, and top-end shift RPM control\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Bikeman Performance","offers":[{"title":"Default Title","offer_id":53717120287013,"sku":"05-120-310","price":27.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0749\/6436\/9701\/files\/05-120-310.webp?v=1788205996","url":"https:\/\/www.bikemanperformance.com\/products\/primary-clutch-spring-120-310-sku-05-120-310","provider":"Bikeman Performance","version":"1.0","type":"link"}