Naraku High Performance V2 Main Torque Spring for 50cc 4-Stroke 139QMB Chinese Honda Cloned Scooters SIZES: 1000 RPM 1500 RPM COMPATIBILITY: Amigo – 50cc 4-Stroke Scooters Apollo – 50cc 4-Stroke Scooters Baotian – 50cc 4-Stroke Scooters Baron – 50cc 4-Stroke Scooters Bintelli – 50cc 4-Stroke Scooters BMS – 50cc 4-Stroke Scooters Coolster – 50cc 4-Stroke Scooters CSC – 50cc 4-Stroke Scooters Diamo – 50cc 4-Stroke Scooters Flyscooter – 50cc 4-Stroke Scooters Ice Bear – 50cc 4-Stroke Scooters Italica – 50cc 4-Stroke Scooters JCL – 50cc 4-Stroke Scooters Jonway – 50cc 4-Stroke Scooters Kandi – 50cc 4-Stroke Scooters Kinroad – 50cc 4-Stroke Scooters KMD – 50cc 4-Stroke Scooters Kymco – 50cc 4-Stroke Scooters Lance – 50cc 4-Stroke Scooters Leike – 50cc 4-Stroke Scooters Linhai – 50cc 4-Stroke Scooters Longbo – 50cc 4-Stroke Scooters Motobravo – 50cc 4-Stroke Scooters Motofino – 50cc 4-Stroke Scooters Motorino – 50cc 4-Stroke Scooters NST – 50cc 4-Stroke Scooters Peace – 50cc 4-Stroke Scooters Puma Cycles – 50cc 4-Stroke Scooters Redstreak – 50cc 4-Stroke Scooters Roketa – 50cc 4-Stroke Scooters Scootstar – 50cc 4-Stroke Scooters Schwinn – 50cc 4-Stroke Scooters SSR – 50cc 4-Stroke Scooters SUNL – 50cc 4-Stroke Scooters Supermach – 50cc 4-Stroke Scooters SYM – 50cc 4-Stroke Scooters Tank Sports – 50cc 4-Stroke Scooters TaoTao – 50cc 4-Stroke Scooters Trailmaster – 50cc 4-Stroke Scooters Veloz – 50cc 4-Stroke Scooters Verucci – 50cc 4-Stroke Scooters Vitacci – 50cc 4-Stroke Scooters Viva – 50cc 4-Stroke Scooters Wolf – 50cc 4-Stroke Scooters Xingyue – 50cc 4-Stroke Scooters ZNEN – 50cc 4-Stroke Scooters GY6 Naraku Performance Torque Springs Naraku Sport V.2 – set of 3 pcs – for 139QMB, GY6, Kymco, Honda, QMB139 Naraku Sports Contra Spring V.2 Pack, +1000, +1500, +2000 rpm The current version of the Naraku counter pressure spring uses a modified alloy spring providing better resilience and above average strength. Torque springs are available in packs of 2 or 3 or are available to purchase individually. Replacing the spring is necessary when tuning engines, the idea is to prevent the initial response from the variator therefore increasing the engine speed, the the increase power with delayed engagement will increase the power at pull off. Markings on the spring help you identify the strength of the spring for example, a spring marked 2000 RPM will delay the reaction by 2000 RPM. The greater RPM spring will provide you with the greater power. **