Blue Line
Blue Line Variator Nut M12x1.25 - 139QMB Scooters
Description
This Blue Line variator nut is an M12 × 1.25 replacement for a broad range of Chinese 139QMB-based 50cc and 80cc scooter applications. It secures the front variator assembly, making it a handy replacement during CVT service when the original nut is missing or damaged. The hex head and integrated smooth-base flange match setups requiring a 23.5 mm overall nut diameter and 8.85 mm height.
Key Features
- Broad scooter compatibility: Suitable for matching 139QMB-based 50cc and 80cc configurations across multiple scooter brands.
- M12 × 1.25 thread: Specific thread diameter and pitch for compatible variator-retaining applications.
- Smooth-base flange: Integrated flange provides the required seating surface.
- Hex-head design: Allows socket engagement during installation and removal.
- CSC fitment: Also fits the OEM variator application on CSC go., go. MAX, Pug 50, and Nitro Sport 50 scooters.
Technical Specifications
- Brand: Blue Line
- Part number: 1200-4003
- Part type: Variator flange nut
- Thread size: M12 × 1.25
- Overall outer diameter: 23.5 mm
- Height: 8.85 mm
- Base: Smooth
- Quantity: 1 nut
Compatibility
For Chinese 139QMB-based 50cc and 80cc scooter configurations that use an M12 × 1.25 variator nut with matching flange seating and clearance. Fitment is based on the installed engine and variator hardware, rather than the badge on the scooter.
| Application | Fitment details |
|---|---|
| Chinese 50cc/80cc engine configurations | 139QMA, 139QMB, 1P39QMB, 1P39QMA-2, YN139QMB, JJ1P39QMB, 139FMA-2, BD1P39QMB, BN139QMB, and 147QMD configurations using the matching nut specification |
| Other QMA/QMB configurations | Confirm M12 × 1.25 thread, 23.5 mm overall nut diameter, 8.85 mm height, and smooth flange seating against the original |
| Chicago Scooter Company | go., go. MAX, Pug 50, Nitro Sport 50 |
Match the original nut and crankshaft thread before ordering. Install to the vehicle manufacturer's torque specification with the variator components fully seated.
Product Diagrams
Features
Specifications
Brand: Blue Line; Part number: 1200-4003; Type: variator flange nut; Thread: M12 x 1.25; Overall outer diameter: 23.5 mm; Height: 8.85 mm; Base: smooth; Quantity: 1; Application: matching 139QMB-based 50cc/80cc scooter configurations and CSC go., go. MAX, Pug 50, Nitro Sport 50
Model Fitments
Brands: Amstar, Amigo, Ascend, Baotian, Bashan, Blade, Boom, Chicago Scooter Company, Dongfang, Roketa, Baotian, Bashan, BMS, Cool Sports, E Ton, Fly Wing, Eagle, Fly, Italica, Riya, Ice Bear, Jackel, Jet Moto, JCL, Taotao, Peace, JM Star, Jonway, Kazuma, Keeway, KMD, Kymco, Lance, Lifan, Linhai, Loncin, Longbo, Fuxin, Jiajue, Tao Tao, Tao Motors, Trailmaster, Maxtrade, Meitien, Motofino, Motorino, NST, Panterra, Panther, Qlink, Yiben, Red Streak, Redcat, Roketa, Schwinn, Strada, SYM, Tank, Terminator ,Tomberlin, TNG, United Motors, Vento, Vitacci, Wildfire, Wolf, X-Treme, X-Pro, Yongfu, ZNEN, Zhongneng , Zhilong, Geely, Wangye, ZH and more Manufactured by: Taizhou Zhongneng Motorcycle Co.; Jiangsu Zhongneng Motorcycle Co.; Jiangsu Meijunte Technology Co.; Taizhou Qianxin Vehicle Co.; Ningbo Dongfang Lingyun Vehicle Made Co.; Taizhou Zhilong Technology Co.; Zhejiang Jiajue Motorcycle Manufacturing Co.; Zhejiang Gelly Ming Industrial Co.; Taizhou City Senglong Motorcycle Manufacture Co.; Jiangsu Sacin Motorcycle Co.; Jiangsu Linhai Power Machinery Group Co.; Zheijiang TaoTao Vehicles Co.; Zhejiang Senling Motorcycle Co.; Sanmen County Yongfu Machine Co; Taizhou Jiaojiang Zhiwei Motorcycle Manufacture Co.; Huzhou Daixi Zhenhua Technology Trade Co.; Taizhou Zhongneng Motorcycle Co.; Zhejiang Riya Motorcycle Co.; Ningbo Longjia Motorcycle Co.; Taizhou Zhongneng Motorcycle Co.; and more
-
Same day shipping for orders placed before 2PM (CST) M-F
-
30-day return period on eligible items
-
Flat-rate shipping for orders shipped to the 48 Contiguous United States.
