250R with only 4200 miles... engine sounds like crap!

[Masospaghetti]

Hey all, first post. My apologies if this is in the wrong forum.

I bought a 2006 Ninja 250 a couple months back, has about 4200 miles now. Engine runs fine, rides fine, sounded fine until today. When the bike warms up, it idles REALLY loud, sounds like valvetrain noise. But only at idle, and only when its hot. Any ideas what could cause this in such a new engine? And no, I didn't run it at 13k rpm for an hour prior to this happening, either.

Thanks

[joelcool]

I wonder if it's still under warranty? You might take it in to the dealer and have them take a peek.

My initial guess would be cam chain tensioner, but don't take that to the bank.

[Masospaghetti]

I don't think its still under warranty...The standard Kawasaki warranty is only 12 months :-(