I got the exhaust fixed. TSC ticked me off a little so I ended up replacing the exhaust myself. BUT WAIT! Does it run?... No. I got it out there and after about 30 seconds of riding, literally, I heard a loud knocking. I thought it was the chain because it was rusting a little, causing it to lock up a little, but I took the chain off and turned the small gear that comes out of the transmission and it was still knocking and locking. What's wrong?