Tapping noise under load?

[Dune Surfer]

I notice when I really gun it up a hill I hear a rat tat tat frome my motor. What do you think it could be? a valve hitting the piston, The 416 piston hitting the XR gasket, The valves out of adjustment, The sleeve slipping and hitting the head?

[bradley300]

is it usually at the bottom of the hill when you are trying to lug it a gear high? my 300 does that in this scenario, as does my 2 riding buddies 400's and every other honda i have ridden.

[13RAZOR13]

Its a streched out Cam Chain slaping around in side or you tensioner is worn and cant take out the slack or both.
Sorry:)

[powerslider]

DETONATION!!!!!!! More octane, valvetrain noise shouldn't be load sensative.

[TrX465]

This could be multiple things first change the oil check to see if it was old or low....if that fails it could be the octane so drain your gas and opt. for higher octane then the last but not least check your cam chain and tensioner... be sure the timing is dead on.. is it hard to start?

powerslider DETONATION!!!!!!! More octane, valvetrain noise shouldn't be load sensative. You got that right and its a motor killer too. If the valves are out of spec they would loud both up the hill and down it and so would the timing chain etc.

Try mixing with some race fuel next time and see what the diff is, bet it goes away unless you now have some mechanical problems.

[bradley300]

like i said, every honda new or old that i have ridden does this when i ride it. atleast when i ride them, the sound sounds like it is coming from the tranny.

Maybe its allways there and the angle of the hill reflects the sound so that you hear it :confused: Or maybe you need to better describe that sound.

[Colby@C&DRacing]

I agree it sounds like detination. A motor that makes that noise under load usually has low octane fuel in it. you really notice it when lugging it up a hill, but don't rule out valve train noise either. We need more info.

[Dune Surfer]

It was a head gasket, Colby talked me through it, I replaced it Sat. It's alive

Wow w should have known that from the "rat tat tat" noise LOL :rolleyes:

But you seriously stumpted us on that one :)

[Dune Surfer]

It's hard to explain the noise it made. I really sounded like metal to metal. Next time I will record it and post it.

:D

[Ricky g]

My 400 made that noise after a butcher shop made an abortion out of a 440 kit.........it is NOT normal, and the quad is not running right, your losing power......I know exactly what that noise sounds like, you hear it when the engine's under load(going up steep hills).......IT IS NOT NORMAL, get it looked at by someone who know's what there doing.

RG

[kat400ex]

what JE piston do you have i have 10/ 8 to 1 and it does the same thing it needs race fuel........octane boost just don't get it.......and a head gasket makes a similiar noise.....its the compression you hear ..that is if the head gasket was blowed ..i just went thur this with mine.....i would only hear it under a load......were putting a big bore kit in it with a 10 3 to 1 je this time......good luck.......it was a 416