While trail riding last weekend my bike began to make a horrendous chattering noise. Thought it may have been a roached chain.....changed out chain and sprockets.....the noise is still there. In first and second gear it runs fine/ no noise. 3rd gear the chatter is bad! Didn't get it in 4/5th but I was not accelerating either. It's getting torn down for sure but I'm looking for input for what to expect. My right side main bearing hole in the case is loose......is it spinning the bearing in the case? Ideas appreciated!