Top End Noise

[bobpara]

I have a 2006 WR 450 with very low hours/miles on it

I just measured the valve clearances and they are all in spec

On the low side of the spec, but still in spec.

 

I have noticed that when I lug the engine through tight single track

I hear a slight noise sometimes coming from what seems to be the top-end of the engine

If I had to venture a guess, it sounds like the cam chain

Does that slipper-shoe and the tensioner need any attention over time?

 

 

[flyandride]

The tensioner takes up the slack automatically and shouldn't need any attention.  You should pull out the cam chain and inspect it for kinks and replace if any are found.  Also it may be worth it to replace the tensioner with a manual tensioner.  Mine made a noise like what you are describing with the manual tensioner adjusted like the instructions said.  I tightened it a little and the noise went away.  

[Alstar450]

Are you sure it's not chain slap? Especially since it occurs when lugging it? Drive chain that is...

[bobpara]

Alstar450: Not sure.....its really hard to diagnose a noise when you are flying along. If I pull in the clutch or let back on the throttle it seems to go away......so I guess that eliminates a loose piece of body work or something. The drive chain is adjusted to what I believe is correct. The noise SEEMS to come from up front, but I cant be sure

[FORMA MOTO]

Noisy, noisy motors

Check to see that your chain is truly in line with both sprockets

Chain slap can be 'cured' by putting silicone under the rub strip

Piston slap is audible at low (3500) rpms as the piston wears

[bobpara]

How long does it take to go from piston slap to crap?

Will the engine pack soon?

[bobpara]

It almost sounds like a bottom end noise, but considering the age & condition of the bike

it seems really unlikely