hello folks. my allegedly low mileage (under 10k miles on the odometer) ninja 250 has opted to have a super loud valvetrain. i was like "ok, i ride at high rpm a lot and adjusted the valves a couple thousand miles ago" and adjusted valves to be in spec. bike was still noisy. removed, cleaned, and reinstalled cam chain tensioner - which was filthy and pitted and stuck. bike ran quietly and then noise returned. installed a new cam chain tensioner. the bike now runs quietly after it starts, then i get intermittently noisy chattering/ticking from the right side of the engine, not as bad as it was, but still not what i like to hear.
i removed the valve cover and cam chain guard, and noticed wear marks on the cam chain guard that covers the top of the chain, just under the valve cover.
please confirm my sanity regarding next steps.
- measure cam chain to make sure it's still in spec. from posts on here seems like ninja 250 cam chains like to get inconsistently stretchy so measuring several points on the chain is the hotness
- if cam chain is in spec, check the cam chain guards that sit vertically inside the tunnel. replace if chewed up / gnarly
- manual cam chain tensioner ???
- if cam chain is out of spec, split the cases, engine rebuild winter™
thanks in advance, this year has been a cornucopia of personal tragedies so i'm dumber than usual