High Performance Two Stroke 70cc Cylinder Kit 47mm 12mm Wrist Pin 40QMB Engines

Part Number SC-IR4740

Affordable 70cc Iron Cast Cylinder Kit for Street Ridding and everyday use.

When Paired with Stage 6 Pro Replica Exhaust or Leo Vince ZXR Exhaust this kit makes a great upgrade for an affordable price. adding a 90/95 jet and air filter rounds it out.

Also we do suggest a larger carb at least 17.5mm. If you are running a 40QMB engine you should have a 17.5 installed. WE do have these with auto choke. Scootertronics has the carbs that come stock on Keeway and CPI scooters which are of good quality. I suggest you up jet to 90/95 main and 45 idle.

Adding the carb and air filter will add enough air flow and gas flow to keep engine cool plus running at top performance.

Of course you can go larger to a 19mm or 2imm dellorto these are even better.

The PWK carbs and flatslide are large physically so they are a little hard to fit when air filters are added, you can add a Bell Mouth with a screen for air intake but you must also have a large exhaust to match.