Valve Noise?

Ok so I'm a newb to the new fourstrokes and just picked up a 2001 YZ426 a couple days ago. I havent really gotten to ride it yet cuz its been so cold here but rode it around a little bit when I bought it. When I got the bike home I started it and let it idle. This may be normal but the valves seem like their making more noise than they should? I heard from someone that it is normal, and that these bikes won't let you start them if the valves are to far out?

Mine have always made some noise when running.

from what ive been told/hear on my yz450 they are really noisey up top (short piston is most of my noise) and yes if the valves get to tight they wont start

I'd check the valve clearance just to be sure. But, all these newer four strokes sound like they have a handful of marbles in them.

The CRF's are the worst...sound like they're coming apart.

There is always going to be noise in top end, its more than likely the cam lobe coming into contact with the bucket.

When you are checking you valve clearance you are checking the distance between the cam lobe and the bucket, the tighter the valve becomes (less distance between cam lobe and bucket) then the less noise the top end will make.

So if you engine becomes quiet then its time to check you clearances. You will notice more noise if you get the valve clearance back to spec than if it was tight.

You will always hear a constant ticking noise. The cam cam lobe hitting the bucket.

Someone flame me if I am wrong.........

your also hearing that short a$$ piston rocking around in the cylinder.

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