I just returned from a 52 mile jaunt in the woods pretty nasty stuff . first ,second, and third gear now and again. Well today during my post ride maintinance i noticed a slight clunking noise during decceleration. It sounds like it is coming from top of cylinder, maby piston,or could it be kips valves? The bike has only 150 or so miles on it. Any ideas? I will take the pipe off to see if it somthing obvious this next weekend. At any case it probably will be spendy.