RK 420 MRU Chain Exhaust Kit includes 2 sets of

Kit includes 2 sets of O-Rings to fit various handlebar inner diameters

5mm with 5mm valve stem exhaust valve -23mm Exhaust port -Matching High Compression Piston -Head kits include all hardware -52mm piston with rings - pin - & clips

This Intake Kit is for adding a 20mm carburetor (with 48mm mounting holes center to center) to your engine

5″ of straight bar for clamp

Structured

RK 420 MRU Chain Exhaust Kit includes 2 sets ofMRU chains utilize RK's proprietary Ultra Thin Seal U Rings which allows the thickness of the seal to be less than 50% of the most common O ring seal MRU features 4 times longer chain life and will require less chain adjustments than comparable non sealed 420 chains Lightweight, low friction, sealed, U Ring 420 pitch chain perfect for Honda Monkey and Honda Grom Tensile strength of 4,540lb 120 Links