2004 GS 500 - Knocking

[GS-Yooper]

I bought a 2004 Suzuki GS 500 F this spring.  The thing was brand new, just a model year out.  Had the first service and the service guy said everything checked out and was up to as he called it, "snuff."  Well as it turns out I am now having a knocking sound in the engine when it idles down to low rpms.  It hadn't made the noise prior to its first checkup.  I know nothing about bikes and the service guy shrugs it off as "normal."  Anyone out there heard of this before?

[Z24_Cavalier]

Check out  there for a cam recall on the 04 05 bikes. Mine had that noise appear after about 1500kms.