Naraku Cylinder 52.4mm 94.9cc 2V Cast Big Bore Kit Duo Combo (139QMB)
Description: High-Quality Naraku Cast-Iron Cylinder 52.4mm 94.9cc with Cast Aluminum Piston offers better durability and reduced friction for 139QMB 49/50cc+ engines. The cylinder bore is 52.4mm. Naraku Cylinders' Combo 52.4mm 94.9cc 2V w/Cast Piston including the following parts Naraku 52.4mm (94.9cc) cylinder kit with cast piston and Naraku oversize 2V head 23/20. Naraku Cylinders' Combo 52.4mm 94.9cc 2V is suitable for all air-cooled 4-strokes, 49-50cc Kymco engines (scooters), and most Chinese imported vehicles 49/50cc (scooters, quads, and buggies).
When used in conjunction with a stock stroke of 41.4mm the engine displacement comes out to 89.3cc! When used with a 44mm stroker crank, engine displacement = 94.9cc!
NOTE: Please, measure with a caliper 139QMB crankcase bore (opening) for 54.5mm cylinder outer diameter sleeve need a minimum 54.6mm bore clearance or boring and machining are required. If, engine case must be bored, order an engine bore tool (Part# 1400-1001). Most stock 139QMB cylinder head's valve height is 69mm which comes standard with its 69mm rockerarm. This Naraku Cylinder Head's valve height is 64mm and will work only with a 64mm rockerarm. If you need a set of 64mm rockerarm see Part# 151-101 sold separately.
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Includes the following Cylinder, Base gasket, Piston, Rings, Piston pin, Circlips, Cylinder head, Head gasket, Exhaust gasket.
1. Includes Naraku Cylinder 52.4mm 2V, Piston + Rings, Gaskets (chain tensioner gasket, base gasket, steelhead gasket, exhaust ring), Wrist pin, and Circlips.
• 1x Cast-Alumin Piston: 51.86mm
• 5x Piston Rings (installed): 52.4mm
• 1x Wrist Pin w/G-clips: 41mm x 13mm x 8mm
• 1x Cast-Iron Cylinder: 52.33mm
• Outer Sleeve Diameter 54.5mm
• Overall Height (w/sleeve): 70.44mm
• Cylinder Height (w/o sleeve): 53mm
2. Includes Naraku Cylinder Head 52.4mm 2V NON-EGR, Valve Assembly.
• 1x Cylinder Head Stud Space: 50mm / H: 60mm / Intake Port: 20.8mm / Exhaust Port: 18.7mm
• 2x Valves: 23x64mm Intake / 20x64mm Exhaust / Stem: 5mm
• Overall Height (w/valves) H: 66.1<67.3mm
• Cylinder Height (w/o valves): 59.75mm
• 6mm Intake Threads
• 6mm Exhaust Threads
• Made in Taiwan
• Fit Intake Studs 6mm
• Fit Exhaust Studs 6mm
• Fit 64mm Rocker Arm Assembly 2V
• Fit 50mm Stud Spacing /Diagonal 70.5mm
• Fit Crankshaft 41.4mm to 44mm
• Fit Dowel Pin Set (8x14mm)
• Fit QMB 49/50cc+
Supported Models: GY6 139QMB 49cc-50cc 4-Stroke engines, Filly 50, Kymco 50, QLink 50, SYM 50, TaoTao 50
Item Weight & Product Dimensions:
• 1.456 Pounds | 4.567" (L) x 4.275" (W) x 2.776" (H)
• 2.193 Pounds | 5.227" (L) x 5.323" (W) x 2.598" (H)