Hi guys new to the forum. Just got my hands on a 08 ds450 and it has a slight knock that goes away as the rpm increase. Any rpm increase makes it go away, even just the extra rpm the bike gives itself on startup makes it go away. Took the valve cover off and there is oil getting to the top end. Cleaned the stain in the oil tank and all the of lines going to and from the motor are clear. My buddy has a 15 ds450 and we put his tensioner in for 20 sec to see if the problem persists and it did...

Can am ds 450 engine knock/slap/tick at idle.