That's short for 'Balanced By BBs'. I've used Dyna Beads for years. At first I thought they sounded like a scam, but they actually work very well. Then I read a post here about using BBs instead. They cost far less than the over priced beads and work just as well. They're also easier to install, recover, and reuse. And they don't get stuck in the valve core. I'm now a convert.
On a related subject, I installed a tire on the spare rear rim for my F6B yesterday. I switched back to Bridgestones, which were the OEM brand, because Avon has raised their prices so high in the new Chromes. I may be switching on the Valks too. I was having trouble seating the beads with my small compressor, so I threw it in the truck and took it to the local tire shop for a bigger shot of air. They had one of those bead seaters that blasts a massive volume of air into the tire in less than a second. I'd never used one before, but what an awesome tool!
Tire shops up north used a 20Lb. propane tank, ball valve and a kind of flattened funnel shaped nozzle for seating tires.
