Greetings, I recently bought a tt600 with 7k and just am getting it serviced because there was a clicking noise that sounded like the valve clearance. After getting the valves adjusted and the throttle bodies synced, the clicking noise still remains. I was wondering what this could be and also, where is the drain hole located on these bikes for the muffler. I noticed a hole on the 1st pipe an inch from where the pipe goes into the header. Is this hole possibly the drain hole?