Hello I'm new in thumpertalk. I'm glad I can ask a question and get answers from very experienced yz owners. I bought 01 yzf 426 in good condition. The previous owner of the bike bought it in Holand after service and didn't make any maintenance. He has riden the bike only 10 times on the fields. It was his first motorcycle so that's why he sold it. (to much power). First I checked valve clerance, two valves are two tight. On intake is 0,9 and one exhaust is 0,13. The chain has no slak it is very stiff. I've tried to move it up and down but it was really stiff. So I think it is preaty new and in good condition. I've took a ride. 50 km on track and in woods. But not forcing the bike. When I was arriving home I heard strange noise while slowing down and engine braking. And when driving on low revs. I thought that it was a chain. But the sound is "faster" and comes from top of engine. When I'm reving the bike the sound disappears. On the neutral it is imposible to hear this sound on eny revs. Also when I put my bike in front of the wall and slowly release the cluch on 1 gear It is imposible to hear anything. Normaly the engine work is really silent. Could you tell me what to do? Change the chain even if there is no play on it?