Somethings loose and it's driving me crazy

[C2H5OH]

2004 XB12R Something is banging every time I hit a bump. The front isolator was worn out and I replaced it. Headers and muffler aren't broken. I've checked everything and can't find anything loose. Battery is strapped down. I did notice it happens when the rear tire hits a bump. To describe the feeling, it would be like someone lightly hitting the engine with a hammer. Any ideas on what else it could be? I'll send a pizza to anyone that leads me to a solution.

[Chicknstripn]

Check your rear wheel bearings, the idler pull and the rear brake system.
Remove your front pulley cover and make sure your belt and front pulley are in good working order.
Last, check that the rear axle it torqued properly and the pinch bolt is present.
Actually, just check all the fasteners guards and what not.
www.buellmods.com
Go to the above sight and download a service manual. That should help you with some trouble shooting.

[C2H5OH]

Found the culprit. At some point the bike had HIDs and they were wired in to the air box. But didn't bother to secure that block of metal that was bouncing all over the place.

airbox.jpg

[TPEHAK]

I attached my stuff with airbox screws

[midway]

TPEHAK, what are all those relays and is that a horn? Horn blowing in the air box must have some funky sound I'd like to hear

[TPEHAK]

The relays are for Motogadget. The horn sounds not so loud, but it is OK.