Hi everyone, I have a 66cc motor with a NT carb and expansion chamber exhaust. When I start the bike, when the engine is cold, it starts up right away. Good throttle response and accelleration. As it warms up, it becomes harder to accelerate, idle, and get moving from a stop. At the end of the ride, it feels as if the clutch is not disengaging because moving the bike becomes difficult. It all returns to normal when the motor cools down after a couple of hours and I start it up again. I'd appreciate any kind of help with this guys, Thank you.