Hey guys, I need some help. I built this bike about 3 weeks ago, and it ran pretty good. My only issue was the chain was making a lot of noise, so I decided to readjust things, take the motor off and lube a few things and then I put everything back together, and now it's much worse. The first thing I noticed was when I went out on a ride, the throttle was much tighter and it was pulling me without me having my hand on the throttle, which was weird because I didn't adjust the cable, but I loosened it way up and now its ok. But, I ran it today and it sounded horrible, VERY loud and much more vibration than before. I came back home, and noticed that there was a black liquid substance on the bottom of the motor. I am going to check the plug color, but anybody have any ideas of what it could be?