The transfer tubes fit snuggly in the grommets that are put in the frame so they don't rattle, thus no beads. It might be possible to install beaded tubes if you could install the grommets into the frame while the tubes are in place. Keep in mind that you'd also have to take the grommets out of the frame before you took the tubes out (hopefully an EXTREMELY RARE occurrence!
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I would never say it doesn't happen, and knowing my ability to screw things up it would happen to me, but I've never heard of a hose coming off one of the transfer tubes.
It sounds like a good idea but IMHO, it's not worth it.