New top end?

So i got a 03 yz 250 a few months ago and when I went to go start it today I noticed a rattling/knocking noise from about a little bit in front of the seat but under the plastics. The bike has a wiseco piston in it but im wondering if that noise is normal or does it need a top end or something like that. Thanks for your help!

Honestly if you bought a used bike I'd pull the cylinder and replace the ring $30 regardless. It only takes like an 1 hr. and is great insurance to prevent any further problems. Plus you could look around in there for play in the rod.

Answers really simple actually, unless the guy gives me reciepts on the top end that was done the day before I always replace the piston and inspect the cylinder before I even kick the bike. You never know how many hours are on a piston and cylinder unless you open the bike and even then thats not a guarentee that the piston is not past its service interval. Also as redneck stated, check the rod for up and down play.

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