Some states will not register the bike without the stickers on the down tubes. Not a problem if you've got the bike registered in your state and are staying put, but if moving to another state, I'd check the registration rules. I was told the state of NJ requires a photo of bike down tubes with the stickers. Mine were off when I got the bike, but it was already registered in NJ, so transferring title was not a problem. I got two new ones from BDM (you have to go through their legal dept). I keep the stickers with the title in an envelope just in case I ever need them when I finally move south. BDM needed a photo of the downtuges and the bikes serial number. It was a real pain in the ass because the photo I sent had a glimpse of my spike air filter and they wouldn't send the new stickers until I replaced it with the original and sent another photo. Fortunately, I had the original air filter and backing plate so I put it on, took the photo, and they sent the new stickers (I think it cost $50 for both). I never did reinstall the spike air filter.