So here is my story, I was finishing a 600 mile ride from Blacksburg VA from the Hog4Hokies ride and noted I was almost at 15K miles and time for service. I dropped of the bike with the following instructions: complete the 15K mile service, check and adjust the clutch (grabbing low), unusual top end noise @ 3000 RPM (sewing machine), squeek in right slip-on, annual state inspection, and hard starting when hot. Results: 15K inspection complete, clutch adjusted (now too high), top end noise explained as normal, no adjustments needed, adjusted slip-on (squeek still there) state inpsection revealed I needed new tires (which I purchased) and the hard starting was due to a bad compensating sprocket. Work performed: Last year the hard starting was explained as starter and replaced under warrenty, now the compensator is the problem due to poor design and has since been upgraded. New tires installed with exact same (Dunlop 407/408). Problem: I now have a new and very distinct vibration around 30 MPH (2nd, 3rd and 4th gear) that didn't exist when I dropped the bike off. I am not sure if it is tire vibration or the new Comp Sproket. I returned the bike to the dealer, the original mech and another mech rode the bike and said there is nothing wrong, normal vibration. I have put every mile on that bike and know what it feels like (and what it is not supposed to feel like) so where could this vibration be coming from? I'm thinking it might be balencing of the new tires but not sure how to determine whether front or rear. In a car, you can determine where the problem is based on where you feel the vibrations, on the wheel it usually indicates balance, in the seat usually something in the rear or in the suspension. Is this also true on bikes? Sorry for such a long first post but I thought the more detail I provide the better someone may be able to assist. Thanks in advance for your advice and if the dealer calls with any info I will add to this.