Ok, Im new with mx-bikes. I bought my first this winter, KTM SX-F 250 ´07. I was doing training on saturday and engine runned ok. Starts ok, works good in every way. But engine noise during ignition cycle got a bit sharper. When I warmed up the engine after washing today to listen it again. I found that engine noise sounded sharper on the right side of the engine than on the left. Could be also my bad ears.. And I found out that exhaust pipe is moving a bit from the root against engine. Should it be fixed stable or allowed to move a bit? I am not actualy sure that has the pipe fractured when I rode or is it "normal". Before mx-bikes I have been in speedway racing and we always sealed the exhaust end from the engine with silicone. I see nothing like that on this engine. Should I try this?