I can not seem to get my nitro rush to stop. I have changed the idle needle like 20 times and that is not the problem. I s the problem my brake disc or something. How can i tell if this is bad i took it off but i dont even know what to look for.

what you should do to find out the prob is to run the car slow enough so you can look over it. then you nail the brake and see what isnt working. then come back and tell me/us what the prob is. you can even put it on a stand and go to full throttle and do this. but remember running the car like that without a load will damage wour engine if you do it for long periods of time.