insane ticking/ tapping/clanging

[fmf400ex03]

my buddy bot a quad that just had a rebuild with a 416 je 10:8 the kid said that he had the vavles replaced and springs he just had them tightend whe n he bought he finished breaking it in and had the valve re tighend and the tapping is insanely loud he has white bros exhaust and u can hear the tapping to the point were the machine doesnt even sound like its running it sounds like u have a 1 foot 8mm bolt and are tapping it against the ground real hard it is awfullhe thought it was the valves but it is wat to loud when u ride it u can still like hear it from like a 1/4 mile away i told him not to ride it and dont touch it but i was woundering what it might be i was thinkin cam or cam shain or rod and bottem end bearing but dunno any other better ideas thank can u right back asap because if it comes out to be real bad he only has like 2-3 weeks left with the lemon law and he will take it to small claims court if its goin to blow up or some thin thank u

[NaturalNoobie]

It sounds like the cam to me.

[Goat397]

is it stroked ?

[04'400ex'er]

Tell your buddy to tear off the plastics and check his valve clearance and adjust the tappetts is needed. that is a pretty extensive project, and there is an article about it in tech reviews with pics. but id just pay 50 dollars and have the shop do it.

[cals400ex]

an aftermarket cam will tick louder than stock in many applications. also, you will probably have different valve clearances with an aftermarket cam, but not always.

[quader400]

it could very well be the valves. once i turned the bolt in the case clockwise and then adjusted my valves and the noise was insanly loud it was a really loud tapping noise make sure you do it counter clockwise im sure thats all it is just readjust your valves you shoud be fine

[UglyMotha™]

a busted timing chain tensioner and a slaping timing chain will cause an insanly loud clainging