CYLINDER KIT 40.00mm STD 01-06 POLARIS 50 SCRAMBLER SPORTSMAN PREDATOR

Complete 40.00 mm top-end cylinder kit for Polaris 50 cc two-stroke youth ATVs, supplied with cylinder, piston, rings, gaskets and cylinder head. Designed for the 50 cc Scrambler, Sportsman and Predator models that use a 40 mm bore, 10 mm wrist pin and 50 mm stud spacing; not suitable for 90 cc engines, which require a 52 mm bore kit.

Features

• Complete kit: cylinder, piston, piston rings, gaskets and cylinder head
• For 50 cc two-stroke Polaris youth engines
• 40.00 mm bore cylinder
• 10 mm wrist pin compatibility
• 50 mm cylinder stud spacing

Specifications

• Engine type: single-cylinder, two-stroke, air-cooled
• Bore × stroke: 40.00 mm × ~39.1 mm (≈49 cc)
• Wrist pin diameter: 10 mm
• Cylinder stud spacing: 50 mm (centre-to-centre)
• Spark plug type: NGK BPR7HS

Cross-Reference OEM Part Numbers

• Cylinder: 0451718 (50 cc applications)
• Cylinder head: 0451717 (50 cc applications)
• Base gasket: 0450008 (50 cc applications)
• Head gasket: 0450003 (50 cc applications)
• Piston (Predator 50): 0453833 (50 cc applications)
• Spark plug: 0450005 (BPR7HS)
• Stud, cylinder/head: 0450010; nuts: 0450011, 0450012
• Cylinder: 0450007 (90 cc/52 mm applications – not for this 40 mm kit)
• Gaskets: 0455372 (base), 0455373 (head) (90 cc/52 mm applications – not for this 40 mm kit)
• Piston kits: 0450802, 0450704, 0450651 (90 cc applications – not for this 40 mm kit)

Vehicle Fitments

• Polaris Scrambler 50 (2001–2003)
• Polaris Sportsman 50 (2001–2003)
• Polaris Predator 50 (2004–2006)

Note: Polaris 90 cc models (Scrambler 90, Sportsman 90, Predator 90) require a 52 mm bore cylinder kit and are not compatible with this 40 mm kit