Vibration and weird sound

[02yuleekay]

Ok so I took my 02 katana 600 to a local bike shop to have them just safety check it and he did a pretty good job so off I went well I rode about 12 miles stopped for about 30-45 min ate and when I got back on I noticed there was a vibration so I didn't really pay to minds too it well after another 8 miles I pick up a girl she hopes on I give her my helmet and we take off still feel vibration but with out helmet on I noticed a funny sound and it's pretty Undescribable Almost if there was a plug out but not idk i hear it when I stick my head under wind screen any common problems I could check or tips to any thing I can do

[Seft]

When were the valve clearances last checked and the carbs balanced?