1986 250SX head noise and jetting questions

[wreckenthusiast]

When idling and when you give it throttle it quite literally sounds like a lathe cutting metal (look it up!). The noise is quiet but noticeable if you listen. It is not obscenely loud but you can tell. It' s kind of concerning, but the thing has had a fair share of ride time and it has not gotten worse. I just really don't like it but have no time to investigate. Anyone have a clue what this could be to point me in the right direction when I one day get to look at it? Also has anyone put a K and N filter on their bike? I need to jet mine because the thing has no balls when you hammer on the throttle and runs too rich, any advice is much appreciated :Bounce

[shortline10]

The most common noise on that model are worn out timing chains and guides .

[wreckenthusiast]

The most common noise on that model are worn out timing chains and guides .

https://photos.app.goo.gl/GxLxN75bP68t9b6D9 heres a video of the noise, thinking about it maybe the cam chain could have totally worn through and is now rubbing on the tensioner? I guess the only way to know for sure is to take it apart... for now it is fine haha ;)

[shortline10]

Easy repair . Check out this thread . If you pull the tensioner just make sure your piston is at top dead center .

https://www.3wheelerworld.com/showthread.php/189806-85-250es-rattling-chain-when-cold?highlight=250sx+tensioner