Holeshot or Ivan's? Both use different methods for the exhaust ports and my Holeshot kit didn't come with any caps for the airbox or intake boot. Holeshot you need to use extreme high temperature silicone to seal the caps, I bought a genuine Yamaha cap and clip for the carb and had to find a cap for the airbox but made sure this was airtight. If you can provide some more information about exactly what you used it would be easier to help you but I'd suggest you've not properly sealed the system.