Chicago Scooter Company
Blue Line Valve Rocker Arm Assembly: 64mm 139QMB Type 1
Description
Keep your 139QMB engine running smoothly with this OEM two-valve rocker arm assembly from Blue Line Designed specifically for Type 1 engines with 64mm valve stems and a shorter cylinder head, this is a direct-fit replacement that restores proper valve actuation and engine timing without modification.
Not sure which type you have? Type 1 engines have 64mm valve stems and a shorter head. If your valve stems measure 69mm with a taller cylinder head, you have a Type 2 engine (made by Zhejiang ZhongNeng / ZNEN) — this assembly will not fit Type 2 engines.
Key Features
- OEM Direct Fit: Exact replacement for Type 1 139QMB engines — no modification required.
- Complete Assembly: Includes rocker arm holder, inlet and outlet shafts, two rocker arms, two tappets, and two nuts.
- Precision Tolerances: Machined to OEM specifications for reliable valve timing and long service life.
- Broad Engine Compatibility: Fits all QMA/QMB engine codes with Type 1 head configuration.
Technical Specifications
- Rocker Arm Holder: L: 66mm / W: 66mm / H: 26mm / Holes: 7.4<9mm / Spacing: 50mm
- Shaft Inlet: L: 51.3mm / OD: 8.8<12.9mm / ID: M5
- Shaft Outlet: L: 43.5mm / OD: 10mm / ID: M5
- Rocker Arms (x2): L: 52.7mm / W: 22.2mm / H: 18.6mm
- Tappets (x2): L: 18.53mm / OD: M5x0.5mm
- Nuts (x2): L: 4.2mm / ID: M5x0.5mm / OD: 9mm
CSC Model Compatibility
| Model |
|---|
| CSC Bella Classic 50 |
| CSC Nitro Sport 50 |
| CSC Pug 50 |
| CSC go |
| CSC go MAX |
139QMB Engine Code Compatibility
Fits 50cc and 80cc engines with the following engine codes (Type 1 head only):
| Engine Codes |
|---|
| 139QMA | 139QMB | 1P39QMB | 1P39QMA-2 |
| YN139QMB | JJ1P39QMB | 139FMA-2 | BD1P39QMB |
| BN139QMB | 147QMD | Other QMA models | Other QMB models |
Don't see your engine code? If it includes "QM" or "FM" and you're running a 139QMB Type 1 engine, this part is compatible.
Product Diagrams
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
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Same day shipping for orders placed before 2PM (CST) M-F
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30-day return period on eligible items
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Flat-rate shipping for orders shipped to the 48 Contiguous United States.
