Blue Line Valve Rocker Arm Assembly: 64mm 139QMB Type 1

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. California Prop 65 Warning: www.p65warnings.ca.gov