NCY Crankcase Decompression Kit - Genuine/GY6

Reduce crankcase pressure and free up power with the NCY Crankcase Decompression Kit. Designed for Genuine Buddy and GY6-based engines, this kit replaces your factory dipstick with a high-flow breather system. By venting excess blow-by gases, crankcase air density drops — allowing the piston to move more freely through less resistant air on each stroke. The result is reduced parasitic drag on the crankshaft, more free-revving engine character, and lower risk of oil burn, blown seals, and gasket leaks. A straightforward upgrade for any performance build or high-WOT application.

Intended for off-road / performance use only. Not for use on public roads.

Features

• Reduces Crankcase Air Density: Venting blow-by gases lowers crankcase pressure, letting the piston travel through less resistant air for measurable power gains.
• Reduces Parasitic Drag: Less crankcase pressure means less drag on the crankshaft and freer engine revving.
• Protects Seals and Gaskets: Proper venting reduces the risk of blown oil seals, oil burn, and gasket leaks under sustained WOT.
• 27" Oil and Fuel-Resistant Tubing: 12mm ID / 18mm OD for flexible routing options.
• CNC Billet Aluminum Cap: Anodized 17mm filler cap/adapter with 18mm thread.
• Complete Kit: Tube, billet cap, stainless steel hose clamps, and zip ties included.
• Installation Tip: Route the breather tube upward toward the frame before pointing it down to prevent oil mist from escaping.

Specifications

• SKU: 1100-1282
• MPN: 633U02H
• Thread Size: 18mm
• Tube Length: 27"
• Tube ID/OD: 12mm / 18mm
• Cap Material: Anodized billet aluminum

Model Fitment