Arai Helmets TDR DUCT-2 Tillotson HW-27A and chin-bar vents

and chin-bar vents

but once installed it is quite solid

or from Rotax

and includes the piston and associated ring to fit in engines that have been bored and adjusted to 53

This micro max engine is designed to be a true performance karting engine for all experienced drivers

Arai Helmets TDR DUCT-2 Tillotson HW-27A and chin-bar ventsThe Arai TDR DUCT 2 Top Rear Exhaust Vent Set is designed to improve the airflow and overall performance of your Arai CK 6, SK 6, or GP 7 helmet. These clear vents seamlessly blend into any helmet design, or they can be painted for a custom look. Perfect for replacing damaged rear ducts, they help maintain optimal ventilation and keep your helmet in top condition. Each set comes ready for easy installation, ensuring your helmet continues to deliver